Fighting with IE 6 - hover

Hello everyone,

I got a problem here building my portfolio ( http://www.laertjansen.com/version02/ ) and I would appreciate if I could get any help here.

The problem is that the square´s over state does not work on IE6. Is there a way to fix it? The CSS is like

.project:hover{background-color:#D1D1D1;}

I don´t know what´s going on on IE7 cause I don´t have it here in this machine.

Thanks a lot in advance for any help.