Hello

When I run my application, sometimes (not always), there is an error message:

Remote Exception : RemoteException occurred in server thread; nested exception is:
java.rmi.ServerException: EJBException:; nested exception is:
javax.ejb.EJBException: null; CausedByException is:
No ManagedConnections available within configured blocking timeout ( 30000 [ms] ); - nested throwable: (javax.resource.ResourceException: No ManagedConnections available within configured blocking timeout ( 30000 [ms] ))

If I have this error, only after I restart JBoss server, the application can run again.

If you know a possible reason, please let me know
Thank you
S.Hoa