platform_new_connection() worked fine, but the really simple stub version for the other ports fell over horribly because I got its name wrong. NEVER ASSUME YOU'VE DONE THE EASY BIT RIGHT. [originally from svn r3166]
(running a local command in a pair of pipes and proxying through that, for example `ssh proxyhost nc -q0 %host %port'). [originally from svn r3164]
