Delivery tolerance at header and item level in sales order

Dear All,

My client wants to maintain delivery tolerance at both header and item level. NOTE: The tolerance at sales order header is different than the delivery tolerance at sales order item.

eg if i maintain 3% plus and minus tolerance at item, the header level tolerance can be 2%.

Also if there are more than 1 line items, the system should give warning message, when it finds that the delivery tolerance at item level can be maintained but that of the header level cannot be maintained and vice varsa.

Awaiting an early help and thankful for the same in advance.

Regards,

Avnesh Kamdar