Interface Builder change text color bug?

I see this happening with the latest version of Xcode as well. Both the Text Color and Background Color controls in the UILabel attribute inspector change at the same time when manually typing in a R G B value, whereas if I choose a color another way (e.g. from the crayons or palette views in the Color picker), only the text color control value changes.

I'd assume this is a bug (and should be filed via http://bugreporter.apple.com), but then again it's persisted through a few versions of Xcode so this may be their expected behavior on purpose. But I'd definitely agree you should file it as a bug.