ETA: Alex Morris (amongst others now) informed me of the CSS3 Gradient Generator v2.0. Looks like it uses a property called
color-stop to achieve the same thing! I haven't used it but it seems cool. If you need to support IE via CSS3PIE, the below method may still may be the way to go.
I'm not sure if anyone else has thought of this yet, so I thought that I might put it out there since it was a problem that eluded me for a few weeks.