button effect - ImageMagick

I'd like someone to write an ImageMagick script either in shell or perl that given a label and a base color, will create a button png with subtle round corners and gradient. The final png will contain 3 buttons stacked vertically shaded differently, that I can use for mouse-over effects. The label will be "embossed" in white, anti-aliased, and centered. I have a png that is an example of the desired result.