Change Windows taskbar colours

I've done some reading, it doesn't look like you can do it without a theme program -- but that program must do it somehow.

I want to keep the XP style (green button deal) but change the colours around, because Windows only comes with blue, olive (ugly as sin) and silver.

Say I wanted an orange start button and a black bar, is this possible?

Edit: I found a solution. It involves patching uxtheme.dll to allow unsigned .msstyle files.