libnotify Plug-In for Gaim
there's is actually a notify plug-in in the repos called guifications.
But this doesn't look any Gnome-like.
So why don't add gaim-libnotify?
Then you would get the same notifications as you already know from other tools.
Source is available here:
Re: libnotify Plug-In for Gaim
I made a deb-package of gaim-libnotify for Edgy Eft, it is inside the archive (see the link)
I put also in: Gaim 2.0-beta5, gaim-libnotify 0.12, gaim-ort 3.0, libotr 3.0 and also gaim-encryption3.0+beta7.
Check if it works for you.