Hi Craig,
The main problem wasn't just the height attrib - there is still a small problem that I didn't see in that you have two unclosed tags in the content div:
<div id="text">' - no closing tags - at lines 175 and 192.
This makes the outerWrapper and contentWrapper appear to be unclosed and nested, and therefore 'containing' (and affecting) the remaining content including the footer.
Remove two instances of <div id="text"> - this clears up the layout nicely and leaves the footer clear, so any margins or padding will apply as it should.
Sorry I didn't spot that earlier.