CloudMade/Leaflet — pull request #600 by DamonOehlman (2012-03-26 04:56:04+00:00)
Title: Tweaked DOM util opacity to only apply in IE when opacity !== 1

Had a few issues working with IE and transparent markers. Essentially, the transparent areas of the markers were being displayed with a black background and disabling the filter style fixed the problem.

Not an ideal fix, I know, but tried a few different things (accessing the msFilter property as per http://www.quirksmode.org/css/opacity.html) but had no luck.