my friend and i are going to have a tournament for quake2 ctf. we want to try to make sure someone doesn't signup with two different teams or something. i was thinking for the player to email us if they wanted to join the tournament. if they use something like gmail rather than a pop3 to email us, it shows the ip of the gmail or whatever server rather than the person's ip. is there a better approach to getting the ip of people who want to join the tournament? thanks!

hi,
u can send all participants an activation link to your site,
u can keep the activation page on SSL protocol,
this will record theri ip for sure,

well i am not sure it will always work cos many people use proxy
but this will work better than just only email approch