More on Tomcat memory problems... this time, the official FAQ. Seems to me they should fix the problems, if they need an FAQ about them.

More searching for answers to out Tomcat out of memory problems... this page suggests setting ULimit to 8192

We're having problems with Tomcat running out of memory, and bringing the server down with it. Setting ULimits might help.

I'm having trouble with 'Out of memory' errors with Tomcat on our productin web server, and I suspect that it's bringing the server down with it. A possible solution is to up the JVM memory heap.