Hello again. Sorry for the verrry late response. We are a very small organization, and couldn't make the time to create a sample EAR or even come here to reply. My apologies.
Well, my problem still exists in the latest version of Glassfish(v2-38), but we've found somethings recently digging around, so I thought I'd share it here.
1. We are using Oracle DB in out project, and we hadn't put a openjpa.jdbc.DBDictionary in the persistence.xml file. GF kept saying that OpenJPA will try to connect to the DB to determine the DBDictionary to use. After adding the property in the persistence.xml file, it seems that we're experiencing much less OutOfMemoryError's.
2. After installing a fresh copy of GF, open the admin console and try to open every menu on the left side. Just click away and open them all from the top. You don't have to change anything, just click away. Did you get to the bottom of the menu list? I couldn't, an OutOfMemoryError was thrown at around Configuration/Security/Realms/file. By looking at the PermGen memory usage in the remotely connected JConsole window, it seems that PermGen usage only grew and was never released. Why? GF is unresponsive after the error, and asadmin cannot stop the server.
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