Error on PO Release APPS 10

Hi All,

We have a Purchase Order that has been raised for a number of zero value “Part Order Lines”, when trying to release this order we get an error message that has not been seen before. 

The error message is: “Only allowed to have charged items together with Delivery Confirmation”

This is not the first PO raised for zero value with this supplier, just dont understand why this order is affected.

Any ideas?

Many Thanks

Steve