1 Exhibit 10.43 September 21, 1999 Mr. Graham G. Pattison 145 Baytech Drive San Jose, CA 95134 Dear Graham: This letter will set forth the agreement between you and Verilink Corporation regarding the relocation of Verilink's San Jose operations to its Huntsville location. In consideration of your managing a successful transition to Huntsville as Verilink's CEO by December 31, 1999, Verilink shall pay you a bonus of $300,000. This bonus shall be subject to applicable withholdings and shall be paid on or before December 31, 1999. Very truly yours, VERILINK CORPORATION By: /s/ John C. Batty, CFO ------------------------ John C. Batty, CFO