GR date

Hello All,

In PO, document date is 12.12.2013 and delivery date is 25.12.2013, during GR if i change the posting date to 10.12.2013 (GR date before PO date) it means that i received the goods before issuing PO to the vendor and that's illogical but the system allow.

i want GR date to be after PO date (12.12.2013) regardless delivery date, i maintained system messages to be an error in case of early delivery date but where to tell the system to check for document date, in other words to specify a tolerance for GR date.

GR date must be greater than PO date and less than or equal to delivery date.

Thanks in advance