CSS positioning help required for a jQuery plugin - jsfiddle example provided

I'm using the following plugin to create a sliding panel: http://samuelgarneau.com/lab/slidebox/

But when I put it on my site, it seems to be in a fixed position, rather than scrolling along with the rest of the site. I've made it up in jsfiddle: http://jsfiddle.net/cYrJB/

I want the "companies" tab to scroll with the site开发者_StackOverflow中文版 - but is just sticks to the top. I think it might be interacting with the fullscreen image plugin I'm using...

I've tried playing with it, and no luck - wondering if anyone can see what I'm doing wrong?

Thank you so much!

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You need to place the companies button and content within the #realBody DIV. The scroll bar for the site is actually on the realBody DIV, not on the body tag. The body never scrolls due to the fullscreenr plugin. Corrected code