Vesterpester

I've had a vanilla Bukkit server for a while, and now since my friend got Technic too, I set up another Hamachi server. I got the server up just fine, but now my buddy can't reach it! I tried to solve the broblem for a while, first I checked that my server was the latest version. Then I checked up my own launcher, and noticed that I had checked the manual build selection. I then upgraded my Tekkit. Tekkit server clearly allows some flexibility with clients version. Well, that didn't help and my friends Tekkit can't still reach the server. I then tried to change Tekkit servers port to something else than default 25565, but it didn't allow even myself to join. I remember when I set up vanilla Bukkit server long time ago, I had to modify the server launch file a bit to support my 64 bitt system. Tekkit servers launch file seemingly doesn't need it. I've also made my friend to double check that hes up to date etc. Now I have no idea what to do. I would really appreciate any tips to get my server running, so we can finally get to play.