REJECTION OF LINE ITEMS IN SALES ORDER ??

Friends !!

1)If there are 10 line items in a sales order two line items should be rejected and the same rejected items should not be displayed in an invoice output? Where will it be configured in IMG. (The items should not be deleted from VA02 it should be is sales order)

2)tell me the process of creating requests in SE10, as there are different module people are working how do they know which request they have created at time of releasing,i have needed detail process step by step.

kindly sent me details plz.

Yours,

Sreedhar