One soloution for this Problem is to change from rpcliteral to documentliteral and useing the unwrap function from wscompile.
However I still wonder why a jaxrpc rpcliteral client unexpect null as a possible return value.
Sorry this Problem is no JBossWS specific,
but I hope I could help some people with the same problem.
How is the associated complex type for
defined in schema?
Does it allow a null value for element result?