5.3 release crash

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I just had a 5.3-release-p2 box crash on me.  This box is in
production so I don't have any debugging information whatsoever. 
However, I'm hoping someone could tell me if what I think caused it is
possible/probable.

Not long before it crashed I was running some stress tests against a
new threaded server I was building in python by running 5-10 clients
simultaneously for about an hour.    Since this box has been stable
for almost a year without any issues at all, I really doubt that it's
a coincidence.   Can anyone think of what issues with threads could
cause a panic?

Chris