Apparently IE 8 cannot change the display of a element to inline-block unless it natively is inline. The fix is to trigger hasLayout on the element before trying to change it. Below is a code snippet to get elements to behave properly in the annoying world of Internet Explorer.
display:inline-block;
zoom:1;
*display:inline;
source: http://foohack.com/2007/11/cross-browser-support-for-inline-block-styling/
keyword: ie 8 inline-block