Production Order with reference to Sale Order.

Hi

The scenario im working on is qty contract. we create a qty contract and then create release orders as and when we get the requirement from the customer. Its a make to order scenario. So once the release order is created with ref to the qty contract, we do an mrp run using md02/md50. Then we create a prod order in Co07/Co08, the prod order is taking the qty contarct as ref instead of the release order(std sale order). When i give the sale order number in co07, the system is throwing an error "Account assignment cannot be carried out because of different origin number".

The details of the error is as follows:

Diagnosis

"The sales doc (release order) to which you want to refer is based on sales doc xxxxx (qty contract). Thesefore the settlemet and possible the inventory management are carried out using the number of the preceding document

procedure

Enter the doc and item number of the preceding doc(qty contarct).

But i want the productio order to be created with ref to the sale order(release order) only.

Please help me with a suitable solution. Also let me know where the assignment is made.

Thanks

Madhu