i haven't tried it yet but i figure before i do i might as well ask...
wouldn't this work?
if ($left($1,4) == /msg) {
echo -a ...theme here
.msg $2-
}
i am a nweb to the max so i really don't know what all this stuff does yet... but im guessing that $left is the left side of the edit box or what not, and 4 would go 4 charecters over i think i just dont want to go and make all of them if they wont work