well i hate be a know it all but i downloaded colornickv2 and it works on my nickname.
i have msn7.5
open a chat window with someone you don't need to talk to them you just need to use the window
you click on color nick and go all the way down to the configurations and choose the gradiant that you want and the linear pattern. then you choose
it will say this
/xcolornick <nickname>
highlight the piece exactly where i coloured then put in your name and press enter when text in the chat box it just disappears. then when you next close it and then open messenger up it should work.
this is correct isn't it or am i wrong
i've never used it before but this is what your looking for)