When MySQL throws a "com.mysql.jdbc.jdbc2.optional.MysqlXAException" when called from a remote client the server thread doesn't seem to be cleaned up of transaction context data. All calls that reusing the thread will fail with the following exception:

org.jboss.util.NestedSQLException: Transaction is not active: tx=TransactionImple < ac, BasicAction: 7f000002:e137:4cf78939:68 status: ActionStatus.COMMITTING >; - nested throwable: (javax.resource.ResourceException: Transaction is not active: tx=TransactionImple < ac, BasicAction: 7f000002:e137:4cf78939:68 status: ActionStatus.COMMITTING >)
at org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:95)
at se.redpill.TestCase3850Bean.runTest(TestCase3850Bean.java:22)
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From what I can see the "MysqlXAException" (implements XAException) will not be caught in "com.arjuna.ats.internal.jta.resources.arjunacore.XAResourceRecord.java". (Can it be some kind of classloading problem?) As the result the thread will not be cleaned of transaction information and "broken" when reused.

This seems only to occur for remote clients (If the client calls within the JVM it seems to work)