Russ,
I had a similar block on the log4j, infact same symptoms, moving it to a a recent version of the log4j has nailed it. If you do a quick search on the tomcat or jboss or log4j archives, you can see loads of queries on this particular locking issue.
If you can try with a later version of log4j, this may get resolved for you too.
cheers
Jeson
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