Oops, i didn't post the config. There really should be an edit button. ' <?xml version="1.0" encoding="UTF-8"?> | <jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:jboss:jbosscache-core:config:3.2"> | <transaction transactionManagerLookupClass="hellotrackworld.impl.srv.AtomikosTransactionManagerLookup"/> | <locking | isolationLevel="SERIALIZABLE" | lockParentForChildInsertRemove="false" | lockAcquisitionTimeout="20000" | nodeLockingScheme="pessimistic" | writeSkewCheck="false" | concurrencyLevel="500"/> | View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4263515#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...