Copy Control - Sales order to Sales Order.. Urgent

Hello SAP Gurus,

Here is the deal , I need to copy the open quantity from one sales order to another sales order. I have already configured the copy control. V_TVCPAAP-PLMIN = "+" and set the flag "Update doc Flow", but that works apparentely for quotation to order and order to delivery.. I tryed to find where the routine 151 does that copy but I counld´ find it. Any help is greatly appreciated.

Thanks

Chico