Oh my God...
I am living in Iran and so far I haven't encountered any restriction from government that would affect playing Teeworlds in anyway. Well the ping to almost all of foreign servers are beyond playable, and thus, the Iraninan servers.
I can not say enough how irritated I am with this whole filtering mess, but why would they filter the master servers of an online game? The master servers, all of them, are accessible from Iran. So what's wrong? Here is what I know:
Until a few weeks ago there were a few Iranian servers working and accessible from the master servers like any other server. They were all from a single IP and from port 8300 to 8309 IIRC. I don't know what happened back then but now they are on port 8000 to 8009 and they are only accessible by direct IP, i.e., they don't register to master servers.
I think there is something wrong with his/her server configuration (sv_register ?). Since he/she does not offer any way to contact him/her on the servers I couldn't contact him/her. Now that I got his/her Email I will try to help solve this problem. And by the way my friend your English sucks which is a shame for the education system.
But... what if we tried more power?