Just wanted to document this in case anyone comes searching. No idea why this bit me now vs before, but I'm pretty sure OpenLog was crashing an ND7.0.3 server (that had with multiple custom fixpacks, if that matters).
The server kept crashing unpredictably, but it was running one specific agent every time it crashed.
Strangely, it didn't crash in the same spot on that agent, nor every time. The agent never ran more than once at a time. Not sure if it's related or not, but the agent happens to be using the now-unsupported mqlsx library, too. (Don't ask.)
Setting NoLSIStackTrace to True seems to have solved it. No more crashes.
Even stranger, several other agents in the same database use OpenLog, and none of them have NoLSIStackTrace set to True. It appears specific to this one agent.
Then again, it could all be a red herring! I'm unwilling to ask our administrator to let me change that agent back to see if that crashes the server some more. :-) I'm pretty sure that the LSIStackTrace calls were the culprit, though.
For anyone new to OpenLog: Use it anyway! It saves a lot of time. Just be aware that if a server does go down, try checking the nsd file and change NoLSIStackTrace to True on any agents that may have been involved.