improved error handling after seeing http://www.nabble.com/ClassNotFoundException-and-distributed-hudson-td22811408.html
improved error handling after seeing http://www.nabble.com/ClassNotFoundException-and-distributed-hudson-td22811408.html

git-svn-id: 28f34f9aa52bc55a5ddd5be9e183c5cccadc6ee4@16841 71c3de6d-444a-0410-be80-ed276b4c234a

oleg-nenashev/remoting,oleg-nenashev/remoting,jenkinsci/remoting,jenkinsci/remoting