
<PAGE>   1
 
                                LEHMAN BROTHERS
                            3 World Financial Center
                               New York, NY 10285
 
                          FUJITSU INTERNATIONAL, INC.
                          A WHOLLY OWNED SUBSIDIARY OF
 
                                FUJITSU LIMITED
 
           HAS INCREASED THE PRICE OF ITS OFFER TO PURCHASE FOR CASH
                     ALL OUTSTANDING SHARES OF COMMON STOCK
                                       OF
 
                               AMDAHL CORPORATION
                                       TO
                              $12.40 NET PER SHARE
--------------------------------------------------------------------------------
 
                 THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT
         5:00 P.M., NEW YORK CITY TIME, ON FRIDAY, SEPTEMBER 12, 1997,
                         UNLESS THE OFFER IS EXTENDED.
--------------------------------------------------------------------------------
 
                                August 22, 1997
 
                     To Brokers, Dealers, Commercial Banks,
                      Trust Companies and Other Nominees:
 
     We have been appointed by Fujitsu International, Inc., a Delaware
corporation (the "Purchaser") and a wholly owned subsidiary of Fujitsu Limited,
a corporation organized and existing under the laws of Japan (the "Parent"), to
act as Dealer Manager in connection with the Purchaser's offer to purchase all
outstanding shares of common stock, par value $.05 per share (the "Shares"), of
Amdahl Corporation, a Delaware corporation (the "Company"), at a purchase price
of $12.40 per Share, net to the seller in cash, without interest, upon the terms
and subject to the conditions set forth in the Offer to Purchase, dated August
5, 1997 (the "Offer to Purchase") as amended and supplemented by the supplement
thereto dated August 22, 1997 (the "Supplement"), and the related Letter of
Transmittal (which, as amended or supplemented from time to time, together
constitute the "Offer") enclosed herewith. The Offer is being made in connection
with the Agreement and Plan of Merger, dated as of July 30, 1997, among the
Parent, the Purchaser and the Company (the "Merger Agreement"). Please furnish
copies of the enclosed materials to those of your clients for whose accounts you
hold Shares in your name or in the name of your nominee.
 
     THE OFFER IS CONDITIONED UPON, AMONG OTHER THINGS, (i) THERE BEING VALIDLY
TENDERED AND NOT WITHDRAWN PRIOR TO THE EXPIRATION DATE OF THE OFFER THAT NUMBER
OF SHARES WHICH, WHEN ADDED TO THOSE SHARES HELD BY THE PARENT AS OF THE
EXPIRATION OF THE OFFER, REPRESENTS AT LEAST 51% OF THE OUTSTANDING SHARES, (ii)
THE EXPIRATION OR TERMINATION OF ANY APPLICABLE WAITING PERIODS UNDER THE
EXON-FLORIO ACT, AND (iii) RECEIPT OF ANY REQUISITE APPROVALS OF THE EUROPEAN
COMMISSION AND THE BANK OF JAPAN. THE OFFER ALSO IS SUBJECT TO THE OTHER TERMS
AND CONDITIONS DESCRIBED IN THE OFFER TO PURCHASE.
 
     Enclosed herewith for your information and for forwarding to your clients
for whom you hold Shares registered in your name or in the name of your nominee,
or who hold Shares registered in their own names, are copies of the following
documents:
 
     1. The Supplement;
 
     2. Revised (yellow) Letter of Transmittal to tender Shares for your use and
for the information of your clients. Facsimile copies of the Letter of
Transmittal (with manual signatures) may be used to tender Shares;
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     3. Revised (beige) Notice of Guaranteed Delivery for Shares to be used to
accept the Offer if certificates for Shares are not immediately available or
time will not permit all required documents to reach the Depositary by the
Expiration Date (as those terms are defined in the Offer to Purchase and the
Supplement) or if the procedure for book-entry transfer cannot be completed on a
timely basis;
 
     4. A revised (blue) letter which may be sent to your clients for whose
accounts you hold Shares registered in your name or the name of your nominee,
with space provided for obtaining such clients' instructions with regard to the
Offer;
 
     5. Guidelines of the Internal Revenue Service for Certification of Taxpayer
Identification Number on Substitute Form W-9; and
 
     6. A return envelope addressed to the Depositary.
 
     WE URGE YOU TO CONTACT YOUR CLIENTS AS PROMPTLY AS POSSIBLE. PLEASE NOTE
THAT THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
FRIDAY, SEPTEMBER 12, 1997, UNLESS THE OFFER IS EXTENDED.
 
     In all cases, payment for Shares tendered and accepted for payment pursuant
to the Offer will be made only after timely receipt by the Depositary of (i) the
certificates evidencing the tendered Shares or a timely confirmation of a
book-entry transfer of such Shares into Depositary's account at one of the
Book-Entry Transfer Facilities (as defined in the Offer to Purchase); (ii) a
Letter of Transmittal (or a manually signed facsimile thereof), properly
completed and duly executed, with any required signature guarantees or, in the
case of a book-entry transfer, an Agent's Message (as defined in the Offer to
Purchase); and (iii) any other documents required under the Letter of
Transmittal.
 
     If a holder wishes to tender Shares pursuant to the Offer, but cannot
deliver such holder's certificates or other required documents or complete the
procedures for book-entry transfer prior to the expiration of the Offer, a
tender of Shares may be effected by following the guaranteed delivery procedures
specified in the Offer to Purchase.
 
     Neither the Purchaser nor the Parent, nor any officer, director,
stockholder, agent or other representative of the Purchaser or the Parent, will
pay any fees or commissions to any broker, dealer or other person (other than
the Dealer Manager, the Depositary and the Information Agent, as described in
the Offer to Purchase) for soliciting tenders of Shares pursuant to the Offer.
The Purchaser will, however, upon request, reimburse you for customary mailing
and handling expenses incurred by you in forwarding any of the enclosed
materials to your clients. The Purchaser will pay or cause to be paid any
transfer taxes payable on the transfer to it of Shares, except as otherwise
provided in the Letter of Transmittal. Backup tax withholding at a rate of 31%
may be required, however, unless the required tax identification information is
provided. See "Important Tax Information" contained in the Letter of
Transmittal.
 
     Any inquiries you may have with respect to the Offer should be addressed
to, and additional copies of the enclosed material may be obtained by
contacting, MacKenzie Partners, Inc., the Information Agent, at its address and
telephone numbers set forth on the back cover page of the Letter of Transmittal.
Inquiries with respect to the Offer may also be addressed to Lehman Brothers
Inc. at the address and telephone numbers set forth on the back cover page of
the Offer to Purchase.
 
                                          Very truly yours,
 
                                          Lehman Brothers Inc.
 
     NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU
OR ANY OTHER PERSON TO ACT ON BEHALF OF OR AS THE AGENT OF THE PARENT, THE
PURCHASER, THE COMPANY, THE DEPOSITARY, THE INFORMATION AGENT, THE DEALER
MANAGER OR ANY AFFILIATE OF ANY OF THEM, OR AUTHORIZE YOU OR ANY OTHER PERSON TO
MAKE ANY STATEMENT OR USE ANY DOCUMENT ON BEHALF OF ANY OF THEM IN CONNECTION
WITH THE OFFER OTHER THAN THE ENCLOSED DOCUMENTS AND THE STATEMENTS CONTAINED
THEREIN.
