Does rsync need UDP ports open?

[Reuben Pearse]

Hi all,

I'm trying to connect across the internet to an rsync server (cwrsync 
running on WinXP) from a Linux box. I have opened up the TCP port 873 on 
the remote firewall and opened a hole in the Windows firewall, but I am 
still getting the error:

rsync: failed to connect to 217.64.121.18: Connection refused

Does rsync use UDP as well?
Does rsync work over NAT OK?

Reuben