So after Damian message, i'm not sure what version i got.
But it is CVS installed the 28/08/04 (using >> use cvs -z5 co -r BRANCH-1-9 tikiwiki for the future 1.9) by my hoster.
I can set the poll, diplay it, etc...
As i vote (i just retest it with another poll) when casting my vote it happen:
An error occured in a database query!
select `optionId` from `tiki_user_votings` where `user` = ? and `id` = ?
I have set the polls to be shown under admin only to avoid everyone getting to it. You want me to set it for anonymous to see it ?