The problem and fix are both quite simple. ;-) Problem: BeanMetaDataDeployer has 2 constructors. The metadata provided in that xml is not enough to make exact/deterministic decision about which constructor to chose. In Carlo's case, he is just lucky that ConstructorInfo is ordered the way it is == matching the right one. Solution: simply add class="org.jboss.kernel.Kernel" to constructor's parameter View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4187363#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...