Alex Shuman wrote:

 >  TK> 2001:470:1f15:cb0:f1d0:2:221:6 119         127.0.0.1       119
 > 
 > BTW, I have tried portproxy to 127.0.0.1 and it does not work. Worked 
 > only with actual ipv4 address, assigned to network card interface.

Oh? Well, please don't tell that to my Win2003server, because that one really 
works here. :) 

tommi@rpi:~$ telnet 2001:470:1f15:cb0:f1d0:2:221:6 119
Trying 2001:470:1f15:cb0:f1d0:2:221:6...
Connected to 2001:470:1f15:cb0:f1d0:2:221:6.
Escape character is '^]'.
200 Welcome to JamNNTPd/Cygwin32 1.3 20180119 (posting may be allowed.)
quit
205 Goodbye
Connection closed by foreign host.

'Tommi
 
--- Sylpheed 3.6.0 (GTK+ 2.24.30; i686-pc-mingw32)