I was having problem with my webservice client generated by wsimport on jBoss 4.2.2. Finally with the help of my boss i fixed it and hopefully will help somebody encountered the same issue as me or myself in the future. I did not know what exactly was happening as seems the exception was suppressed and could not be seen in the catch cause. But fixing it I actually was just copying library into jboss-4.2.2GA\lib\endorsed. 1. Download JAX-WS 2.6 and copy below files: Gmbal-api-only.jar Jaxb-api.jar Jaxb-impl.jar Jaxws-api.jar Jaxws-rt.jar Policy.jar Stax-ex.jar Streambuffer.jar into jboss-4.2.2GA\lib\endorsed. (Please refer to https://developer.jboss.org/thread/214201?tstart=0) 2. Copy below files: jboss-jaxrpc.jar jboss-jaxws.jar jboss-saaj.jar into jboss-4.2.2GA\lib\endorsed. (Please refer to http://leakfromjavaheap.blogspot.hk/2013/03/jboss-422-ga-to-jdk-7-or-jdk-6-migration.html) After copying the ja...