Fixing a infinite loop problem when a signature confirmation is sent with no values

git-svn-id: https://svn.apache.org/repos/asf/webservices/wss4j/trunk@1587570 13f79535-47bb-0310-9956-ffa450edef68
Amending last commit

git-svn-id: https://svn.apache.org/repos/asf/webservices/wss4j/trunk@1587571 13f79535-47bb-0310-9956-ffa450edef68