Dynamic Skin Modifier Problem? HELP!

Hello All!

I wanted to use the Dynamic Skin Modifiers in order to give different "identity" to the avatars populating my game. I encountered a serious problem though:

I am having multiple instances of AIPlayer using the same datablock, running around in my game. The first time I try to mask their skin is working fine: i.e

Avatar1.addSkinModifier(0, "torso", "base", "mask", "255 0 0 255");
Avatar2.addSkinModifier(0, "torso", "base", "mask", "0 255 0 255");

However, when I invoke

Avatar1.addSkinModifier(0, "torso", "base", "mask", "255 255 0 255");

BOTH Avatar1 AND Avatar2 are masked with the color (255 255 0 255)!

I will appreciate ANY tip!

Thanks a lot in advance!

Nina