The deploy tool option "--deploymentplan" is explained as: "Takes the deployment plan, which is a JAR containing Sun-specific descriptors, and deploys it."
I 'm already using this option to provide the deployment process with a sun-application.xml file, which contains the 'context path' of the web module. I didn't walk the 'trial&error' path yet with this issue (still trying to get the available infos before "hacking around" for days), so I didn't try to pack another persistence.xml into the deployment-plan-jar. I didn't try because the above documentation clearly states that the deploymentplan contains 'Sun-specific' descriptors -- which is not true for 'persistence.xml' (JPA standard, not server specific).
For me it it not clear from the documentation I found, what kind of files are permitted as part of the 'deployment plan jar' (and evaluated by the glassfish server at deployment time).
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