you can also see the behaviour for yourself if you visit the site, scroll down & click the 'Demo' button (it'll take you to the page). but you'll have to set your monitor to 1024x768 i think
regarding a solution, i'm thinking of either putting some giant padding on the div's (id=question or something) or setting a minimum height for the div/divs. & then targeting IE7 only with the * hack, & maybe another approach for targetting safari. is this sensible?
i don't know why the problem is arising, so i thought i'd ask in case anyone knew. a problem understood being a problem avoided in future & all that