every page on my board is fully reloading on IE7 \ 8.
 

my forum url is - www.iatraf.co.il

when browsing with IE 7 \ 8 each page reloads from the beginning (blank for a mili sec and then the entire page loads) it doesn't happens with FF \ Chrome.

I mean that the header should not reload, but you can definitely see that the entire page reloads instead of just the content block under the header.

Do you know what can cause such thing or how can I fix it?

Thanks.