Problems with $ (''). height ();

My site is basically like this:

img http://www.mediafire.com/convkey/3266/gr3pg3kqokxkkduzg.jpg

I make the following script to keep block #right from height of #left:

$('#right').height($('#left').height());

But when I put some content in the left block, the right block gets a little smaller:

If you want to see the site: link

How do I do it?

Thanks in advance!