problem with % in IE8?

when the below link is viewed in IE8, the middle column overlaps on left column, this is fine in IE7, FF 2and 3..
I doubt its because the left column is given width in %??

link (http://www.limoinc.net/more-about-joomla.html)

When do we actually use % and px ?

Make sure you remove any blank lines before the doctype. I notice one in your code.