Who said anything about Windows? The concept of a remote procedure call is much older than Microsoft, and Sun had RPC to support NFS while Windows was still thinking about how to implement TCP....
You're still probably best off with a good EULA and legions of lawyers.
~Mike. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/