Using a test program i am posting emails via JMS. A Single MDB will upload an attachment to ftp server and will send the email. the test program will post messeages , creating a single thread.
I discoverd that the JMS gets disconnected from the provider.
Following is the error i am seeing.
Caused by: org.jboss.util.NestedSQLException: No ManagedConnections available within configured blocking timeout ( 30000 [ms] ); - nested throwable: (javax.resource.ResourceException: No ManagedConnections available within configured blocki