PA leaving foreign currency balances in UNB/UNE

 Our international office bills in many currencies.  As you know, PA invoices hit the GL via AR as multi-currency journal entries.  The PA revenue entries to the GL are not multi-currency journal entries and are just in the currency of the SOB (in this case EUR).  Over the course of a project the EUR balances in the UNB/UNE accounts net to 0.  However, the USD, GBP, and other currency balances from the AR postings remain.  When they run a foreign currency trial balance they have big balances in these accounts.  Is there any way to correct this other than entering