Search Bar Compatibility Issues with Internet Explorer

Using the Commons Origins theme, the search bar breaks in Internet Explorer. The drop-down that allows a user to select if they want to search a specific group or the entire site doesn't function. This forces the user to only be able to search specific areas depending on where they are in the site (the default location that the search bar presents).

See a live example on: http://commons.acquia.com

Could this please be fixed so that the drop-down functions properly? This issue occurs in both IE7, IE8 and IE9.

Thanks!