Different themes for personal messages.

[kat]

I have an SMF forum of my own and I also use several others.

Quite a few of the members are colour-blind/confused and have asked if it's possible to have a different theme, for using PMs, so it's easier for them to distinguish between them and normal boards.

I can't imagine that it's possible, now. Is this something that can be done via a mod, or do we have to code something, seperately?

EDIT:

Having looked at InstantMessage.template.php in the default theme, could a theme, such as "Babylon" be made the default for personal messages?