Improper alignment of fluid children of fixed ancestors in IE7

Created by: lyndsysimon

I seem to have broken the fluid layout in IE7, and simplified it down to the point that I think it is a bug in Bootstrap.

jsFiddle: http://jsfiddle.net/tinkerer/mM9Ke/

Spans of 2,3,8,9, and 10 all bump the last element onto the last line when using all 12 columns in a child fluid row.

I'm using IE8, set to IE7 Standards Mode via the development console.