Font glyphs rendering incorrectly

The font glyphs appear to be grabbing to large of an area or are shifted up. I have noticed this in a number of widgets and menu items. Only certain characters appear to be affected and similar artifacts appear under similar characters (e.g. "F" always has the same artifact appearing underneath). I have attached screen captures of the "Text Edit" example using the 4.6.2 build and 4.7 build (latest code from gitorious). The glitches can be seen in the menus and in the the text edit. It also appears in the about dialog (I have attached a screen shot of the 4.7 about dialog). I have only tested this on Windows, so I am not sure if it appears on any other OS.