http://opensimulator.org/mantis/view.php?id=4040 by jhurliman. The patch didn't match up, so I winged it here. My effort to manually merge the patch seems to make sense, so I'm going to commit it.
* If you have something using XmlRpc that isn't in core, change your method signature from:
(XmlRpcRequest request)
to:
(XmlRpcRequest request, IPEndPoint remoteClient)
Added OpenSim.Grid.UserServer.Modules project/dll which now contains the components of the userserver. With the OpenSim.Grid.UserServer being the setup and initiate exe.