[tor-talk] Why tor doesn't support UDP?

[Yuri]

It is well known that tor only supports DNS UDP requests, and not other UDP.

Tor could relay UDP through the same path as TCP. And the chosen exit 
node could act as a UDP gateway, much like regular routers relay UDP 
packets from different LAN hosts. Routers substitute source port of UDP 
packets and later map back the ip/port in response packets. It could be 
easily imagined how tor could do just the same.
When I use the virtual machine connected to network through the tor, 
only http apps work, and all UDP apps fail. Even skype is unable to connect.

So what is the reason that UDP isn't supported?

Yuri