Your numbers are similar to what I see on openSUSE 11.2 for glassfish with only hudson.war deployed.
In my case:
Heap: ~200MB
Non-Heap: ~140MB
JVM committed virtual-memory: ~1GB
One thing that we should note is that committed memory (the 1GB above) is memory that is guaranteed to be available to the process (JVM in this case), but not necessarily being "used". If the 1.2GB that you quote is committed memory, then I wouldn't worry about it too much.
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