iweb iframe - scrollbar doesn't appear

Hi guys,

I have recently got my head around the basics of iweb and have developed my website (a work in progress). I wanted to include a forum and after a bit of research went with YABB forums. I read that you could install the forum onto your server and then just create an iframe in which to put it so that it doesn't look like you are leaving the site when you click on the page. So i did all this and it seemed to work but no matter what i do, I can't see a scroll bar when navigating around the site in the iframe. It proves impossible to use the forum as the bottom of a lot of pages are missing. please take a look:

http://www.cabnine.com/forum.html

This is the code I'm using in the iweb iframe:

<IFRAME SRC = "http://www.cabnine.com/cgi-bin/yabb2/YaBB.pl" WIDTH="975px" HEIGHT="1090px" FRAMEBORDER="0" --if "0" no border, otherwise "1" with border MARGINWIDTH ="0px" MARGINHEIGHT="0px" SCROLLING="yes" --"no" no scrolling bar, "yes" show always, "auto" showed when need > Your browser does not support IFRAME </IFRAME>

Any help would be hugely appreciated.