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                                   CORE, INC.
                       AMENDMENT OF 1991 STOCK OPTION PLAN


         WHEREAS, CORE, INC. (the "Company") maintains its 1991 Stock Option
Plan (the "1991 Plan");

         WHEREAS, the Company's 1991 Plan permits the Board of Directors of the
Company to make such changes in and additions or amendments to the 1991 Plan as
the Board shall deem advisable;

         WHEREAS, the Board of Directors deems it advisable and in the best
interests of the Company to amend the 1991 Plan to clarify the treatment of
outstanding options upon the sale, merger, reorganization or other
recapitalization of the Company;

         WHEREAS, the Board of Directors has determined that the following
amendment is consistent with the 1991 Plan prior to amendment and does not
adversely affect the rights of any holder of outstanding stock options.

                  1. Section 11 of the 1991 Plan is hereby amended so that, as
                  amended, it shall read in its entirety as follows:

                  "11. ADJUSTMENTS UPON CHANGES IN CAPITALIZATION, STOCK SPLITS,
                  MERGERS, ETC.. Notwithstanding any other provisions of the
                  Plan or any Stock Option, in the event of any stock dividend,
                  recapitalization, merger, sale of all or substantially all of
                  the assets or outstanding equity, consolidation, liquidation,
                  dissolution, split-up, combination or exchange of shares, or
                  similar change in the outstanding Common Stock of the Company
                  by reason of the foregoing or similar transactions (in each
                  case a "Transaction"), the Board may make appropriate
                  provisions, adjustments and amendments relating to the Plan
                  and outstanding Stock Options, including, without limitation
                  adjustments and amendments to (i) adjust the aggregate number
                  and class of shares available under the Plan, (ii) adjust the
                  number and class of shares subject to each outstanding Stock
                  Option, (iii) adjust the Stock Option exercise prices, (iv)
                  substitute the consideration payable to the Company's
                  stockholders for each share of Company stock in a Transaction
                  (or other consideration of similar value as determined by the
                  Board) ("Stockholder Consideration per Share") for each share
                  of stock issuable upon exercise of a Stock Option and (v)
                  terminate outstanding Stock Options in exchange for a cash
                  payment or other consideration equal to the excess of the
                  Stockholder Consideration per Share over the Stock Option
                  exercise price. The provisions, adjustments and amendments
                  made by the Board pursuant to this Section 11 shall be binding
                  and conclusive."

         IN WITNESS WHEREOF, the undersigned has executed this Amendment as of
the _____ day of March 2001.

                                                 CORE, INC.

[CORPORATE SEAL]

                                                 By: /s/ George C. Carpenter IV
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