No...
There are some dirty workarounds you can do, but they never work perfectly (or not at all
) and the biggest concearn (that strange people will still be able to see your msn email) will not be prevented with these kinds of workarounds.
It is an issue which needs to be addressed by microsoft itself for a proper fix.
anyways, lots of threads about this already. Always search forums before posting. eg, see:
*
People Adding Me to 3-ways
*
How do I disable auto accepting a chat invite?
*
Group-Conversation Warning(Version 0.5)
(read the full threads)