Inconsistent writes to a data queue

For a month in our testing, we have been having some odd behavior with a new app that feeds a data-queue.
We are occasionally missing a QSNDDTAQ entry to the data-queue and have not yet been able to explain it.
We have now reported it to IBM, but I wonder if anyone else has seen this problem.

The application is a vendor's maintenance screen to change a master budget file that is surrounded with an OPNQRYF.
When the budget is changed, a trigger program is invoked to feed the data-queue with QSNDDTAQ.
And the Data-Queue Entry is then picked up by a Sharepoint C# program that is part of a Sharepoint Workflow which reads the data-queue using the Toolbox apis.

What is happening on the iSeries is an inconsistent behavior - - the QSNDDTAQ is not feeding the data-queue consistently.
Debugging the program has not surfaced anything, and in the next line after the QSNDDTAQ, a write to a database file that mirrors the data-queue confirms the file-triggers have been working the whole time. Likewise, MIMIX journals are showing the hit on the Data-Queue. (In acuality, MIMIX does a SAVOBJ to move the DataQueue to our hot box.)

We have also been using the Craig Rutledge DSPDTAQ utility to confirm entries and today, we have confirmed that the missing entries occur even when we don't use DSPDTAQ.
So we are stumped with this whole problem.
( Is it a problem with QSNDDTAQ is not multi-threaded-safe or something like that ? )

John Voris, Information Services
Crown Americas LLC