Hi
What is the concept? An accrual for expected payments for sales? If the answers to my questions is yes, create a statistical conditions, set the accrual in the pricing procedure and determine any field in the FI item with the key of sales employee with the help of an enhancement (see Note 301077 - User exits for the interface to accounting for further information, see EXIT_SAPLV60B_005 in this note, it's for accruals).
I hope this helps you
Regards
Eduardo