[HUDSON-5048] Fixed the multi-classloader support in the remoting code. I confirmed that this fixes HUDSON-4993 without modifying the warnings/analysis-core plugin.

I'm letting Hudson run the whole test suite to see if there's any regression caused by this.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@24490 71c3de6d-444a-0410-be80-ed276b4c234a