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                                                                    Exhibit 3.28

                   Certificate of Incorporation of ELBO Inc.

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                          CERTIFICATE OF INCORPORATION

                                       OF

                                    ELBO INC.

                                   * * * * * *

     1. The name of the corporation is:

                                    ELBO INC.

     2. The address of its registered office in the State of Delaware is 103
Foulk Road, Suite 200, Wilmington, Delaware 19803, located in the County of
New Castle, Delaware. The name of its registered agent at that address is Entity
Services (Delaware), Inc.

     3. The nature of the business or purposes to be conducted or promoted is:

          To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

     4. The authorized capital stock of the Corporation shall consist of 100
shares of capital stock with a par value of $.01 per share.

     5. The name and mailing address of the sole incorporator is as follows:

          Sally P. Schreiber
          Klehr, Harrison, Harvey, Branzburg & Ellers LLP
          1401 Walnut Street
          Philadelphia, PA 19102

     6. The Corporation is to have perpetual existence.

     7. In furtherance and not in limitation of the powers conferred by statute,
the Board of Directors is expressly authorized to make, alter or repeal the
By-Laws of the Corporation.

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Elections of Directors need not be by written ballot unless the By-Laws of the
Corporation shall so provide.

     8. The Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Certificate of Incorporation, in the manner now or
hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.

     9. A Director of the Corporation shall not be personally liable to the
Corporation or, its stockholders for monetary damages for breach of fiduciary
duty as a Director except for liability (i) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the Director derived any improper
personal benefit.

     I, THE UNDERSIGNED, being the sole incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the General Corporation Law of the
State of Delaware, do make this certificate, hereby declaring and certifying
that this is my act and deed and the facts herein stated are true, and
accordingly have hereunto set my hand this 27th day of May, 1998.


                                        /s/ Sally P. Schreiber
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                                        Sally P. Schreiber,
                                        Sole Incorporator


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