[Plugin: NextGEN Gallery] Lightbox doesn't works :-/

Hello there !

I’m using the last version of NextGen Gallery and the lightbox effect doesn’t works anymore. I don’t think it happens after an update… here the link for my website :

http://hassisol[dot]fr/wp2011/

Do you have an idea of where the matter come from ?

Thanks you all !!!

http://wordpress.org/extend/plugins/nextgen-gallery/