Hi, I realize this thread is quite old but I too am having the same problem testing the hello-world BPEL service. And the resolution quoted does not appear to work for me. So I wondered if anybody could help me still. My problem is exactly the same 'serialVersionUID' class incompatible issues for the ....QName class. I have a root directory: with the following sub directories installed: jwsdp-2.0 jbpm-bpel-1.1.Beta3 jboss-4.0.4.GA I have a JAVA_ENDORSED_DIRS system variable set to: ...\jwsdp-2.0\jaxp\lib; ...\jwsdp-2.0\jaxp\lib\endorsed I am running from a JAVA_HOME of jdk1.5.0_11 with the same version jre. thanks Phil View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4014935#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...