AUC_RESP_BID_NULN functionality incorrect for no bid response.

When an event has been created with "Quantity Not Applicable" selected on AUC_LN_DTLS_PG, and responders click the "no bid " check box on the AUC_RESP_BID_NULN page unintentionally then go back uncheck the no bid checkbox on the AUC_RESP_BID_NULN page, enter their unit price and go to the start page, error messages are appearing stating: Quantity Required. Quantity not found for line 1 - there is no plce to put a quantity for the line because the event was set up with "Quantity Not Applicable".  Has anyone seen this problem before if so, is there a fix for it.