Can click but doesn't count

Hello !
I’m trying to use this plugin, but it seems it won’t work… I can click on the image rating (who haves the css :hover), I can’t click twice (alert js) but It’s not rating, I’ve nothing in the rating manager.
I’ve tried with the lastest version and also with the previous, but still nothing…

Somebody can help me ?

http://wordpress.org/extend/plugins/wp-postratings/