Thanks guys, you've both been very helpful and you have deduced the cause & confirmed my workaround by the looks.
For the record, this app server instance startup/shutdown is begin controlled by Solaris SMF, with the service properties being created the 'asadmin create-service' functionality. This calls the appropriate 'stop-domain' etc - The server is always shutdown cleanly using this and never with a TERM/KILL or whatever - all as you'd normally expect.
With the info. you've provided I've believe I've found the bug, it looks like this one - Issue #7180 :
https://glassfish.dev.java.net/issues/show_bug.cgi?id=7180
Which is fixed in v2.1.1 build 25 (July 29 2009).
I will put the workaround in place for the meantime and hopefully a planned future upgrade will just sort this problem out correctly.
Thanks again
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