Field INTRASTAT_EXEMPT is mandatory for PO and requires a value

We applied 3 patches to our Apps 10 UPD 10 environments last weekend that should not have impacted creating Purchase Orders, but we are now receiving the error message ‘FIELD INTRASTAT EXEMPT IS MANDATORY AND REQUIRES A VALUE’  when we try to save a PO for several US Suppliers (so Intrastat Exempt should not even come in to play. )

Just to see if checking that checkbox would fix it, I tried but still received the error.  Tried with several other Suppliers/PO and about have received the message when trying to save the PO and half were allowed to save the PO successfully. I can not see any differences in the set up of the Suppliers  that worked and the suppliers for whom I received the error when saving a PO. 

Anyone else seeing this? 

Is this a bug? 

Thanks