Try using the GenericTransactionManagerLookup in your JBossCache configuration. This should detect the WebLogic transaction manager.
Regarding your code, looking up a UserTransaction is the correct way to get a hold of a transaction instance so this is correct as well.
Thanks for your response.
So, my understanding is I should set TransactionManagerLookupClass to org.jboss.cache.GenericTransactionManagerLookup in the tree cache configuration file and access this transaction with:
UserTransaction tx=(UserTransaction) new InitialContext().lookup("javax.transaction.UserTransaction");
Is this correct? Thanks again.