How to dynamically replace a specific color w/in a .png file

Hello,

I'm working on a UI that is using embedded .png files for art assets. I don't like the current color and instead of brute forcing a change by modifing all the .png files via a image editor I'd like to be able to dynamically change the color when it is drawn via a mxml parameter (or similar global variable). I only need to do this once upon startup, but don't want to show the old color then have it visiably replaced with the new but instead just display the new color. I am using Flash CS3 and Flex (but didn't see a newbie Flex thread).

I've read some post that seem to suggest converting the images into MovieClips and setting the Color property on the movie clip but I don't know if this will replace all color with the new ones verses replacing a certain color with the new one.

It seems like I'm overlooking something simple and I wanted to ask before doing the work to convert the images over to MCs.

Thanks in advance for any help! :)

Paul