Also, I wrote a simple test case, and got some unexpected behaviour. I started a tx in the first vm, then checked if a node 'existed'. Then, from another VM, I added data to that node. Back in the original VM, I added data to a node and called commit. I was expecting some sort of rollback exception, but instead it overwrote the value that the 2nd VM had placed in the node. To me, this appreas incorrect. Any ideas on something i'm doing wrong? Thanks again for the help. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4011673#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...