This PR [1] removed exclude for xmlbeans in Websphere distribution, so it is now included in WAS distribution which causes conflicts with xmlbeans that is read from IBM JDK which is used by WAS. See stacktrace here [2] and here [3]. You can reproduce this behaviour by using web service work item on WAS.

[1] https://github.com/droolsjbpm/kie-wb-distributions/pull/392/files
[2] http://pastebin.com/JBthF0yg
[3] http://pastebin.com/hKHjD9Cn