2.1.1 and Fixed Nav Dropdowns on IE8 and IE7 not overflowing the navbar

Created by: oller

I'm having a problem which has only cropped up since upgrading from 2.1.0 to 2.1.1

A fixed-nav dropdown on IE7 and IE8 now doesn't seem to appear.

The root of the problem seems to be the overflow: visible !important rule in the respnosive stylesheet is not being read by IE7 and IE8 as it's within a media query they ignore. So the dropdown menu does not overflow the navbar and therefore barely appears.

Anyone else had / noticed this issue?