Yes, the gremlins strike again, as a user on my UI beta forums so nicely put it. gChat and many other similar chat addons are having issues due to the very changed functionality of the chat frames in WoW patch 3.3.5.
I was working on a new and updated version to deal with this, but I did not manage to finish it in time. Blizzard don't really tell us when their patches are coming. Ever.
Now, I have actually a version that kind of works, but it's unfinished as it still has some issues regarding whispers.... which I can NOT solve for another week, since Blizzard in all their wisdom decided to only release the patch on US realms, not on EU realms.
Anyway, without further delay, I give you the unfinished beta of gChat 1.5;
But do remember to only download this if you're playing on a client with the 3.3.5 patch. If you're not, stick with the 1.4x versions.