
                                  Exhibit 4-2
                                                       WARRANT NO. PW/A-12

                               PURCHASE WARRANT

                  30,000 SHARES OF ACC CORP. $.015 PAR VALUE
                             CLASS A COMMON STOCK


      FOR  VALUE  RECEIVED,  ACC Corp., a Delaware corporation (the "Company"),

hereby grants to Columbia Capital  Corporation  (the "Holder"), with an address

of 201 North Main Street, Suite 300, Alexandria,  Virginia  22314,  the  right,

subject to the further terms and conditions set forth herein, to purchase  from

the Company 30,000 whole, fully paid and nonassessable shares (the "Shares") of

its  $.015  par  value  Class  A  Common Stock at a purchase price per Share of

$16.00 (the "Purchase Price").  This  Warrant shall be fully exercisable on its

date of issuance and in all events shall  expire  and be of no further force or

effect at the earlier of the time when it has been  exercised  with  respect to

all  Shares  which the Holder is entitled to purchase hereunder or 11:59  P.M.,

New York City  time,  on  the  date  which is three and one-half years from the

issuance date hereof (the "Expiration  Date").  The number and character of the

Shares  and  the  Purchase  Price  are subject  to  adjustment  as  hereinafter

provided.  As used herein, this "Warrant"  means  and includes this Warrant and

any  Common  Stock  purchase  warrant  of  the  Company  hereafter   issued  in

substitution  for  or  in  replacement  of  this  Warrant  or  to  evidence the

continuing  effect  of  any  part  of  this  Warrant after any partial exercise

hereof.

      1.    EXERCISE.  This Warrant may be exercised  in whole, or in part from

time  to  time,  by  the  Holder by delivering this Warrant  together  with  an

executed Subscription Agreement  in the form annexed hereto as Exhibit A to the

Company or such person as the Company  may  have appointed as warrant agent, at

its  principal  office  (or at the office of the  agency  maintained  for  such

purpose), accompanied by payment by certified or bank check or wire transfer of

funds payable to the order  of the Company, in an aggregate amount equal to the

per share Purchase Price as then adjusted multiplied by the number of Shares as

to which this Warrant is then being exercised.  The Company or such agent shall

cancel this Warrant on any such  exercise  and,  if  such  exercise is partial,

shall  issue  and deliver to the Holder a new Warrant upon the  same  terms  as

contained herein  with  respect  to  the  unexercised  portion of this Warrant.

Anything in this Warrant to the contrary notwithstanding,  this Warrant may not

be exercised after the Expiration Date and may be exercised  only  with respect

to whole Shares.

      The  Company  will,  or  will  direct  its  transfer  agent  to, issue  a

certificate  or  certificates  for  the  number of fully paid and nonassessable

Shares as to which this Warrant is so exercised,  and in lieu of any fractional

shares to which the Holder would otherwise be entitled,  pay cash equal to such

fraction  multiplied  by  the  Purchase  Price  as then adjusted,  as  soon  as

practicable after any exercise of this Warrant, and  in  any  event within five

business days thereafter, at the Company's expense (including the payment by it

of any applicable issue taxes), in the name of, and deliver the  same  to,  the

Holder (on payment by the Holder of any applicable transfer taxes).

      Notwithstanding  the  preceding  paragraph,  any  Shares as to which this

Warrant  is  exercised shall be deemed issued on and as of  the  date  of  such

exercise in accordance  with the first paragraph of this Section and the Holder

shall thereupon be deemed to be the owner of record thereof.

      All shares issued pursuant  to  any  exercise  of  this  Warrant shall be

"restricted securities" within the meaning of the Securities Act  of  1933,  as

amended  (the  "Act")  and the rules and regulations thereunder, and shall bear

the standard restrictive  legend  under  the  Act.   Upon  any exercise of this

Warrant,  the  Holder  shall  also  execute  the form of representation  letter

attached as Exhibit B hereto making the representations regarding the status of

the Shares contained therein.

      2.    ADJUSTMENTS.

      (a)   STOCK DIVIDENDS, SPLITS, ETC.  The  number  of  Shares  that may be

purchased on exercise of this Warrant and the Purchase Price therefor  shall be

proportionately  increased  or  decreased,  as  the  case may be, for any stock

dividend,  stock  split, combination, subdivision or other  changes  made  with

respect to the Class  A  Common  Stock  of the Company at any time prior to the

Expiration Date.  An adjustment made pursuant  to  this paragraph shall, in the

case  of  a  stock  dividend or distribution, be made as  of  the  record  date

therefor and, in the  case  of  a subdivision or combination, be made as of the

effective date thereof.

      (b)   REORGANIZATION, RECAPITALIZATION,  CONSOLIDATION, MERGER OR SALE OF

ASSETS.  In the event of any reorganization or recapitalization  of the Company

or  in  the  event  the  Company  consolidates  with  or  merges  into  another

corporation  or  transfers  all  or  substantially all of its assets to another

entity, the Holder, at any time after  the consummation of such event, upon the

exercise of this Warrant and payment of  the Purchase Price as provided herein,

shall be entitled to receive the stock to  which  the  Holder  would  have been

entitled  on  such  consummation  if  the  Holder  had  exercised  this Warrant

immediately  prior  thereto.   In  such  case, the terms of this Warrant  shall

survive the consummation of any such event  and  shall  be  applicable  to  the

shares  of  stock  receivable  on  the  exercise  of  this  Warrant  after such

consummation.

      3.    NOTICES  OF RECORD DATES, ETC.  The Company shall mail or cause  to

be mailed to the Holder,  at  the  same  time  it  mails  such  notices  to its

shareholders  of  Class  A Common Stock, all notices specifying any record date

for shareholders of its Class  A  Common  Stock  with  respect to any dividend,

distribution or right, or with respect to any shareholder meeting to be held at

which  a vote is to be taken for the purpose of approving  any  reorganization,

recapitalization,    reclassification,    consolidation,    merger,   transfer,

dissolution,  liquidation  or  winding up of the affairs of the  Company.   The

Company also shall provide to the  Holder  all  notices  and  reports  that  it

provides to its shareholders generally.

      4.    TRANSFER OF WARRANT OR SHARES.

            (a)   TRANSFER  OF  WARRANT.  Neither this Warrant, nor any part or

right with respect to it, shall be  sold, transferred, assigned or hypothecated

other than in accordance with Section  6  hereof.   Before selling or otherwise

disposing of this Warrant or any part thereof (in any  case  in accordance with

the  terms hereof) the Holder agrees to give 10 days' prior written  notice  to

the Company  of  its  intention  to  do  so.   The  notice  shall describe with

particularity the proposed transfer.  If, in the reasonable opinion  of counsel

to  the  Company,  such transaction may lawfully be effected under the Act  and

under any other applicable  Federal  or  state  law  or regulation, the Company

shall then permit the Holder to sell or otherwise dispose  of  this  Warrant or

portion thereof in the manner described in the notice given to the Company.

            (b)   TRANSFER  OF  SHARES.   Should  the Holder desire to sell  or

otherwise dispose of any Shares acquired upon the exercise of this Warrant, the

Holder  shall  notify the Company of the terms of such  transaction  and  shall

comply with the  requirements  contained  in  the  form  of  investment  letter

attached  as  Exhibit  B hereto.  If, in the opinion of counsel to the Company,

such transaction may lawfully  be  effected  under  the Act and under any other

applicable Federal or state law or regulation, the Holder  shall be entitled to

sell or otherwise dispose of such Shares in the manner described  in the notice

given to the Company.

      5.    REPLACEMENT   OF   WARRANT.   On  receipt  of  evidence  reasonably

satisfactory to the Company of the  loss,  theft,  destruction or mutilation of

this  Warrant,  and,  in the case of any such loss, theft  or  destruction,  on

delivery of a bond or other  indemnity  reasonably satisfactory to the Company,

or, in the case of any such mutilation, on  surrender  and cancellation of this

Warrant, the Company shall issue a new Warrant, of like  tenor  in lieu of such

lost, stolen, destroyed or mutilated Warrant.

      6.    TRANSFERS.   The  Holder  represents by its acceptance hereof  that

this Warrant is being acquired for investment  and  not  with  a  view  to  the

distribution  thereof.   The  Holder  shall not transfer or assign this Warrant

except  (a)  in a transaction which is permitted  under  applicable  securities

laws, or (b) by  will  or  pursuant  to  laws of descent and distribution.  Any

attempted or purported assignment or transfer of this Warrant not in compliance

with this Section shall be void.  The Company shall cause to be kept a register

of the Holder(s) of this Warrant (the "Warrant Register").  In the event of any

transfer permitted by this Section, the Company  shall or shall cause its agent

to register the transfer or assignment on its Warrant  Register on surrender of

this  Warrant,  duly  endorsed,  or  accompanied  by  a written  instrument  or

instruments of transfer in form reasonably satisfactory  to  the  Company, duly

executed  by  the  Holder  or  by  the  duly appointed legal representative  or

attorney-in-fact thereof.  On any such registration  of  transfer,  the Company

shall  issue  a  new  Warrant  or  Warrants,  of  like  tenor,  in  lieu of the

transferred  or assigned Warrant.  Notwithstanding the foregoing provisions  of

this Section,  this  Warrant may be surrendered to the Company, together with a

written  request for exchange,  and  thereupon  the  Company  shall  issue  and

exchange therefor  one  or more new Warrants, of like tenor as requested by the

Holder,  and the Company shall  cancel  this  Warrant  on  such  surrender  for

exchange.   In  no  event,  however, will the Company be required to effect any

registration of transfer, assignment  or  exchange  that  would  result  in the

issuance  of  a  fraction  of  a share.  For purposes of this Warrant, the term

"Holder" shall refer to all persons  who  at any time are listed in the Warrant

Register as holding a Warrant representing any portion of the rights hereunder.

      7.    REGISTRATION OF SHARES UNDER THE  ACT.   At  any  time prior to the

Expiration  Date  of  this  Warrant,  and  subject  to  the further limitations

contained  in  this  Section,  the Holder(s) shall be entitled  to  demand  and

receive one registration, under  the Act and the laws of the State of New York,

of all but not less than all of the  Shares  acquired or acquirable pursuant to

the exercise of this Warrant in full, as follows:

            (a)   To  initiate  the  registration,  the  Company  must  receive

written requests for such registration from the Holder(s) of all of the Shares.

            (b)   Upon receipt of such request(s), the Company shall:

            (i)   Use its best efforts  to  promptly  cause  to be prepared and

      filed with the Securities and Exchange Commission (the "SEC")  under  the

      Act and also filed with the applicable New York State authorities, within

      45  days  following  receipt of such request(s), a registration statement

      (the "Registration Statement") and prospectus or post-effective amendment

      (the  "Amendment")  to  the   Registration   Statement  relating  to  the

      distribution of such Shares;

            (ii)  Use  its best efforts, through its  officers  and  Directors,

      auditors and counsel  to cause the Registration Statement or Amendment to

      become  effective at the  earliest  practicable  date  after  the  filing

      thereof;

            (iii) Deliver  to  the  Holder(s)  such  number  of  copies of such

      prospectuses in preliminary and definitive form, and amendments  thereto,

      as such Holder(s) may reasonably request; and

            (iv)  Keep  effective such Registration Statement, make such  other

      filings related to  it,  and  do  such  other  acts  and things as may be

      reasonably necessary in the opinion of counsel for the  Company to permit

      the public sale or other disposition of such Shares for a  period  of  90

      days after the effective date of such Registration Statement or Amendment

      as the case may be.

      The Company's obligation to commence such a demand registration set forth

in  subparagraph (b)(i) above is subject to deferral for a period not to exceed

90 days  if  such deferral is deemed necessary or appropriate by counsel to the

Company.  In lieu  of accepting such deferral, however, the Holder(s) may elect

to cancel their registration  demand  and  exercise such right at a later date,

but in no event later than the Expiration Date of this Warrant.

      The Company will also cooperate with the  Holder(s)  and their respective

counsel with respect to any registration or other qualification  of  the Shares

by the Holder(s) for sale under the securities or "blue sky" laws of up to five

jurisdictions,  in  addition  to  New  York  State,  as  such  Holder(s)  shall

reasonably  designate  and  continue its cooperation with respect to such state

registrations or qualifications  so long as reasonably required for the purpose

of sale of the Shares.

      The  Holder(s)  likewise  shall  cooperate  fully  with  the  Company  in

effecting such registration.

      The Company shall pay all fees,  taxes, and expenses pertaining to filing

a Registration Statement or Amendment with  the  SEC  and  with New York State,

including  but  not  limited  to,  Federal and New York State registration  and

filing  fees, fees and expenses of the  Company's  counsel  and  auditors,  and

printing, mailing and other distribution expenses incident to such Registration

Statement  or  Amendment.   The  Holder(s)  selling Shares in such registration

shall be responsible for all state "blue sky" expenses in all states other than

New  York  State, all underwriting fees and expenses  and  all  fees  of  their

counsel and accountants.

      In the  event  that  the  registration shall for any reason other than an

act(s) of the Holder(s) not become  effective,  or if the Company shall fail to

keep such registration effective for the period of  time  set forth above, then

such  attempted registration shall not be deemed a registration  hereunder  and

the Holder(s)  shall continue to be entitled to a registration pursuant to this

Section.

      The Company  shall  indemnify  and  hold  harmless  each  Holder and each

"underwriter" within the meaning of the Act who may purchase from  or  sell for

any  such  Holder  any  portion  of  the  Shares  (and each person, if any, who

controls  any such Holder or underwriter) from and against  any  and  all  such

losses, claims,  damages,  liabilities and expenses (including reasonable costs

of investigation) joint and  several  to  which  they or any of them may become

subject under the Act or otherwise and, except as  hereinafter  provided,  will

reimburse  each  such  Holder  and each such underwriter for any legal or other

expenses incurred by any of them  in connection with investigating or defending

any  claims  or actions, insofar as such  losses,  claims,  damages,  expenses,

liabilities or  actions  arise  out  of  or  are based upon any misstatement or

alleged misstatement of a material fact contained in any registration statement

under  the  Act  or  any  prospectus included therein,  or  any  amendments  or

supplements thereto, which  is  filed or furnished by reason of this Section or

arise  out of or are based upon any  omission  or  alleged  omission  to  state

therein  a material fact required to be stated therein or necessary to make the

statements  therein  not  misleading,  except  insofar  as such losses, claims,

damages, expenses, liabilities or actions are caused by any  such  misstatement

or omission made in reliance upon and in conformity with information  furnished

to the Company by or on behalf of any such Holder or underwriter expressly  for

use  in  connection therewith.  The indemnity agreement in this paragraph shall

be in addition to any liability which the Company may otherwise have.

      In order  to provide for just and equitable contribution in circumstances

in which the indemnification provided for in this Section is unavailable to any

Holder or underwriter  under the Act or any person who controls any such Holder

or  underwriter  (collectively,   "Indemnified   Parties"),   the  Company  and

Indemnified Parties shall contribute to the aggregate losses, claims,  damages,

and   liabilities  of  the  nature  contemplated  by  said  indemnification  in

proportion  to the relative fault of the Company and the Indemnified Parties in

connection with  the  statement  or  omission that resulted in such damages and

other  relevant  equitable  considerations.    The   relative  fault  shall  be

determined  by reference to, among other things, whether  in  the  case  of  an

untrue statement  or  alleged omission to state a material fact, such statement

or omission relates to  information  supplied by the Company or the Indemnified

Parties and the party's relative intent,  knowledge,  access to information and

opportunity  to  correct  or prevent such untrue statement  or  omission.   The

amount paid or payable by an  Indemnified  Party  as  a  result  of the losses,

claims, damages or liabilities referred to in this paragraph shall be deemed to

include  any  legal  or  other expenses reasonably incurred by such Indemnified

Party in connection with investigating  or  defending against or appearing as a

third  party  witness  in  any  such  action or claim.   No  person  guilty  of

fraudulent misrepresentation within the  meaning  of  Section  11(f) of the Act

shall  be  entitled to contribution from any person who is not guilty  of  such

fraudulent misrepresentation.

      The Company's  agreements  with  respect to this Warrant or the Shares as

stated in this Section shall continue in  effect regardless of the exercise and

surrender of this Warrant.

      8.    RESERVATION OF SHARES.  The Company shall at all times reserve, for

the purpose of issuance on exercise of this  Warrant,  such  number of its duly

authorized and unissued and/or treasury shares of Class A Common  Stock or such

class  or  classes of capital stock or other securities as shall from  time  to

time be sufficient  to  comply  with  this  Warrant.   If,  at  any  time,  the

authorized  and unissued and/or treasury shares of Class A Common Stock or such

other class or  classes of capital stock or other securities are not sufficient

for the exercise  of this Warrant, the Company shall take such corporate action

as may in the opinion  of  its  counsel be necessary to increase its authorized

and unissued and/or treasury shares of Class A Common Stock or such other class

or classes of capital stock or other  securities  to  such  number  as shall be

sufficient for that purpose.

      9.    SURVIVAL.    All   agreements,   covenants,   representations   and

warranties  herein shall survive the execution and delivery of this Warrant and

any investigation  at any time made by or on behalf of any party hereto and the

exercise, sale and purchase  of  this  Warrant  and  the  Class  A Common Stock

issuable on exercise hereof.

      10.   SHAREHOLDER RIGHTS.  This Warrant shall not entitle the  Holder, as

such, to any voting rights or other rights as a shareholder of the Company,  or

to any other rights except the rights stated herein.

      11.   NOTICES.   All  demands, notices, consents and other communications

to be given hereunder shall be  in  writing and shall be deemed duly given when

delivered personally or three days after  being mailed by certified first class

mail, postage prepaid, return receipt requested,  properly addressed, if to the

Company at: 400 West Avenue, Rochester, New York 14611, or if to the Holder, at

its  address set forth above.   The Company and the  Holder  may  change  their

respective  addresses  at  any  time  or times by notice given hereunder to the

other.

      12.   AMENDMENTS; WAIVERS; TERMINATIONS;  GOVERNING  LAW; HEADINGS.  This

Warrant  and any term hereof may be changed, waived, discharged  or  terminated

only by an  instrument in writing signed by the party against which enforcement

of such change  waiver,  discharge  or  termination is sought.  The corporation

laws of the State of Delaware shall govern  all  issues concerning the relative

rights of the Company and its shareholders.  All other questions concerning the

construction, validity, enforcement and interpretation of this Warrant shall be

governed by and construed and interpreted in accordance  with the internal laws

of  the  State  of  New  York, without giving effect to any choice  of  law  or

conflict of law provision  or  rule  of any jurisdiction.  The headings of this

Warrant are for convenience of reference only and are not part of this Warrant.



Dated:  July 21, 1995                           ACC CORP.

Witness:
                                          By:  Michael R. Daley
/s/ Francis D.R. Coleman
Secretary                                 Title:  EVP & CFO


<PAGE>
                                   EXHIBIT A

                                 SUBSCRIPTION


       (To be completed and signed only on an exercise of the Warrant.)


TO:  ACC CORP.:


      The undersigned, the Holder of the  within  Warrant,  hereby  irrevocably
elects to exercise the purchase right represented by such Warrant for,  and  to
purchase thereunder, _______ shares of the Class A Common Stock of ACC CORP. to
which  such  Holder  is  entitled  thereunder,  and  herewith  makes payment of
$_________  therefor  in  cash  or  by  certified or official bank check.   The
undersigned hereby requests that the Certificate(s)  for  such shares be issued
in his name and delivered to the following address:








      If the foregoing Subscription evidences an exercise of the within Warrant
to purchase fewer than all of the Shares to which the undersigned  is  entitled
under  such  Warrant,  please  issue  a  new  warrant,  of  like tenor, for the
remaining Shares in his name, and deliver the same to the same  address  as set
forth above.


Dated: ______________, 19___.       ______________________________
                                          (Name of Holder)


                                    ______________________________
                                          (Signature of Holder or
                                          Authorized Signatory)

<PAGE>
                                   EXHIBIT B


TO:   ACC CORP.
      400 West Avenue
      Rochester, New York  14611

Gentlemen:

      In  connection with the issuance to the undersigned of _______ shares  of
the Class A  Common  Stock  (the  "Shares")  of  ACC  CORP.  (the "Company"), I
understand that the Shares have not been registered under the Securities Act of
1933,  as  amended,  (the  "Act") by reason of a specific exemption  under  the
provisions of the Act which  depends  upon my representations contained in this
letter  and  that  you  are  relying on such  representations  as  a  condition
precedent to permitting the issuance  of  the  Shares to me.  I also understand
that any sales made by me publicly under Rule 144 can only be made after I have
held the Shares for two years, and then only in  limited  quantities  and  only
under  the  terms and conditions of said Rule; and that any other public resale
of the Shares  may  require  registration  under  the Act or compliance with an
exemption from the registration requirements of the Act.

      I  agree  that the Shares may not be transferred  unless  and  until  the
Company shall have been informed of the proposed transfer and:

      1.    A registration  statement  with  respect  to  the  Shares  shall be
effective  under  the  Act,  and  I  shall have furnished satisfactory proof of
compliance with any other applicable law; or

      2.    I  have  obtained  an opinion  of  counsel,  in  form  and  content
satisfactory to the Company and  its  counsel,  that no violation of the Act or
any other applicable law will be involved in such  transfer,  and/or such other
documentation  in connection therewith as counsel for the Company  may  in  its
reasonable discretion  require  as  a  condition  precedent  in order to make a
determination that the transfer will involve no such violation.

      I  agree  that  appropriate  legends  may  be  placed on any certificates
delivered to me representing the Shares in order to give notice of the transfer
restrictions  set  forth  in this letter and that the Company  may  cause  stop
transfer orders to be placed on my account.

      I further acknowledge  and  agree that neither the Company nor any of its
agents, officers or directors have  made  any  representations  concerning  the
Company  or  its  prospects  and  that  I have based my decision to acquire the
Company's stock upon information furnished  to  me  by  persons  other than the
Company, its officers, directors or agents.

      In consideration of the transfer of the Shares to me, I hereby  agree  to
indemnify and hold harmless the Company, its officers, directors, employees and
agents,  from  and against any and all liability, losses, damages, expenses and
attorneys' fees which any of them may hereafter incur, suffer or be required to
pay  by  reason  of  the  falsity  of,  or  my  failure  to  comply  with,  any
representations contained in this letter.

                                          Very truly yours,


                                          ______________________________
                                                (Signature of Holder)

                                          ______________________________
                                                       (Date)



