Im having this same problem.. my web.xml file its ok.. and the web app and jpa seems to be ok either.. but when i try to deploy.. :/
The full stack follows below..
org.eclipse.core.runtime.CoreException: Deployment Error for module: darf: Exception while loading the app : java.lang.RuntimeException: EJB Container initialization error%%%EOL%%%Exception while invoking class org.glassfish.ejb.startup.EjbDeployer load method : java.lang.RuntimeException: EJB Container initialization error%%%EOL%%%
at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishDeployedDirectory(SunAppServerBehaviour.java:750)
at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishModuleForGlassFishV3(SunAppServerBehaviour.java:591)
at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishModule(SunAppServerBehaviour.java:281)
at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publishModule(ServerBehaviourDelegate.java:948)
at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publishModules(ServerBehaviourDelegate.java:1038)
at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publish(ServerBehaviourDelegate.java:872)
at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publish(ServerBehaviourDelegate.java:708)
at org.eclipse.wst.server.core.internal.Server.publishImpl(Server.java:2690)
at org.eclipse.wst.server.core.internal.Server$PublishJob.run(Server.java:272)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
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