We discovered a problem when mass-deleting large numbers of records (as when clearing notes or transactions), and fixed it prior to the notification of the Service Pack for Receivables. However, there was a version of Receivables with this problem on our web site for a few days, and it sounds as if your clients were "eager beavers" and downloaded the update. You can fix the problem on their site by downloading the Srvice Pack again and re-installing it.

Sorry you ran into this - we don't think there are many people affected (in fact, we thought it possible that no one was affected), and the impact of the problem is small (items that you are trying to delete don't get deleted).