Poll voting isue

Hiya all i have a php based logon system and advanced poll system installed on site but now my problem: you can vote mulitple time while i need my users to only vote one time is there any way i can couple a vote with a username ? like that if the script sees that a user allready voted it disalows him to vote our can advanced poll be zet to this that it dus not alow multiple voting's ?

Regards,
Scotty

In your admin/general settings... down in the miscellaneous section, set the lockout timer to however many hours you want to keep the users from being able to vote again.