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                                                                EXHIBIT 10.12-01

                      STOCK OPTION AGREEMENTS SERIES A

         The Stock Option Agreements Series A, each dated as of September 18,
1996 between the Company and the following employees are identical in all
material respects to Exhibit 10.12 except with respect to the number of shares
which are subject to the option:

         1.       Robert B. Terry, Jr.;
         2.       Robert F. Mecredy;
         3.       Juan de Ledebur; and
         4.       Gregory F. Echols

         The Stock Option Agreement Series A, dated as of September 18, 1996
between the Company and David A. Apseloff, is identical in all material respects
to Exhibit 10.12 except with respect to (i) the number of shares subject to the
option and (ii) and additional provision in Section 2.2 (e) which provides that
if Mr. Apseloff's employment is terminated by the Company prior to the first
anniversary of the agreement, but after the consummation of the IPO, his option
shall be exercisable with respect to 16 2/3% of the shares of Common Stock
subject to the option.

         The Stock Option Agreements Series A, each dated as of September 18,
1996 between the Company and following employees are identical in all material
respects to Exhibit 10.12 except (i) with respect to the number of shares which
are subject to the option, and (ii) that the Agreements do not provide for
monthly vesting of the option:

         1.       Jeffrey Marlin;
         2.       Geoff E. Lonsdale;
         3.       Christopher Bailey;
         4.       Wenlong Tsang;
         5.       Bradley D. Nichols;
         6.       William E. Tait;
         7.       Charles L. Belitz;
         8.       Frank Socolow, Jr.
         9.       Gregg A. Rowland;
         10.      John D'Araujo, Jr.;
         11.      James W. Hall;
         12.      Lifan Hua;
         13.      Michael J. McKean;
         14.      Michael A. Wenson;
         15.      Rameshchandra Patel;
         16.      John A. Morelli;
         17.      Robert J. Combs;
         18.      Robert A. Dare, Jr.;
         19.      William E. Jordan, Jr.;
         20.      Robert Rivers;
         21.      Christopher S. Bryan;
         22.      Theresa A. Reed;
         23.      Darcey Tatum;
         24.      Ed Schumacher;
         25.      Wen Li;
         26.      Charles Kenyon, Jr.;
         27.      David F. Pritchett;
         28.      Michael Leonhardi;
         29.      Donald W. Harvey; and
         30.      Larry David Walker.
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         The Stock Option Agreement Series A, dated as of December 23, 1996
between the Company and Charles N. Bowen, is identical in all material respects
to Exhibit 10.12 except (i) with respect to the number of shares which are
subject to the option and (ii) that the Agreements do not provide for monthly
vesting of the option.

         The Stock Option Agreements Series A, each dated as of December 30,
1996, between the Company and the following employees are identical in all
material respects to Exhibit 10.12 except (i) with respect to the number of
shares which are subject to the option and (ii) that the Agreements do not
provide for monthly vesting of the options:

         1.       James S. Parker; and
         2.       Christopher K. Scullion.