In case anyone gets this error and cannot figure it out. Using the standard installers you will likely end up with 3 spots referencing your datasource. Unfortunately I was only updating 2 of them. I had missed jbosscmp-jdbc.xml, hence the reason using an XA datasource seemed to get me along further. Anyways with the standard install changing to a datasource named MSSQLDS I would recommend the following changes. C:\jboss-4.2.3.GA\server\default\deploy\ejb-deployer.xml change datasource from jboss.jca:service=DataSourceBinding,name=DefaultDS to jboss.jca:service=DataSourceBinding,name=MSSQLDS C:\jboss-4.2.3.GA\server\default\deploy\jbpm\jbpm-service.sar\hibernate.cfg.xml change from java:JbpmDS to java:MSSQLDS also change from org.hibernate.dialect.HSQLDialect to org.hibernate.dialect.SQLServerDialect C:\jboss-4.2.3.GA\server\default\deploy\jbpm\jbpm-enterprise.jar\META-INF\jbosscmp-jdbc.xml change from java:/JbpmDS to java:/MSSQLDS View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4217633#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...