I have just downloaded wild west multiplayer demo form here
http://au.conitec.net/ and I triedto play online with my friend.I hosted he tried to join to server.But he saidthat his game cant find servers even I hosted.I tried to make other otions in config.txt but result is same.

Maybe you have to forward a port at your router.

One thing you must ALWAYS do is make sure your firewall is ALLOWING the port to be opened. It may ask you to Block/Unblock the program's features the first time you try to connect. If so, click UNblock. If not, go to Control Panel, and then go to firewall. Add an exception for the program to be able to make connections on the proper port (TCP). If that doesn't work, follow Razoron's advice and fully forward the port, step by step. If you have further trouble, Google your router and try some troubleshooting. You'll get it!

At the end of the multiplayer tutorial under "Hosting an online gmae", there is a description how to set up a server:

http://www.conitec.net/litec/work25.htm