RokTab Content Display Issue

I have used roktabs in one of my website to display the content.
The content is the roktabs is taking too much time to display in the browser.
This is happening in IE both 7 and 8.
The difference of time for the content loading in the 2 browsers is very large.
It does not show any error in the page and also the page gets completely loaded, but the content does not appear.