Shoutbox

My brother realized recently that hes able to change the skin of his messenger window. So he changed it to lightning.       But this in turn also changed to that skin for me as well and i find it quite hard to read anything with that one.      And when i change it back it also changes back for my brother.       

So i would love to know, is it possible to have different skins for different email accounts?    or better yet different Messenger Plus! preferences for the both of us?     If so PLEEEEEAS tell me how!