I can connect to my own server. but when my friend trys to connect it says "Failed to connect to server, its probally down"

i port forwarded 25566 and changed it in my server settings (my brother already used 25565)

http://www.minecraft.net/play.jsp?server=ab4caac9a0d7eb65cc3d7e353b80fbf5   thats my server (not up right now)



Help? i want my friend to connect