Cannot View Supporting References

We have set up supporting references for Invoice, Credit Memo, and Debit Memo transactions in Payables.  We have run the Create Accounting process from Payables and posted the journal entries.  We query on the journal and click in the line that contains the AP Distribution Account, then click on the Line Drilldown button.  In the View Journal Entry Lines window, we click on the Supporting References button, and it returns, " Error Page:  You have encountered an unexpected error. Please contact the System Administrator for assistance"

Any ideas why this would happen?