If I remember, you just comment out the JBossTX manager and uncomment the Tyrex manager in the jboss.jcml file.
Thanks! But the default configuration file of tyrex that comes with JBoss (domain.xml) does not contain any valid info. I could not find any sample configuration file from Tyrex website or documentation too. Also any idea where to find the documentation on how to use the Tyrex Transaction Manager? I just can't find it from the Tyrex website to download files. Thanks in lot!