I've committed some changes to CVS to fix this. BigDecimal and BigIntegers are now marshalled as String values. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3977736#3977736 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3977736