Biztalk 2006 Tracking Missing

Hello BizTalkers,
I have a problem with Biztalk 2006:
Sometimes it happens that a message is handled perfectly, but the entry in Health and Activity Tracking (HAT) is missing. This has occured for a very low number of messages so far, but it is rather critical to us.
I did some research on this topic and noticed, that when using the "Recently Sent Messages" query in HAT, the outbound message is shown as expected, but it is not possible to browse to the inbound message, because there is a hyperlink missing in there, which is available for all the other messages. In all cases, the message routing worked correctly from receive port to send port, but only HAT entry is missing.
Did some further research: in the BizTalkDTADb database there is a row missing in the MessageInOUt table (or something similar) for the message-id in question. From this point on, I gave up …
From my point of view, this is a bug in the Biztalk Tracking feature. Has anyone else experienced this problem ?
Best Regards,
Florian