Dragging users in the 'edit buddies' window leaves horizontal lines behind. This is with gaim 0.10.3-1 from rawhide. There should be a category for gaim rawhide in bugzilla, since it's moving into main for the next release.
This really looks like a gtk bug to me. The icon for the drag window is destroying the lines underneath it and they aren't being repainted properly. It's using a ctree and I'm pretty sure that all that drag code is in the ctree itself. Right, guys?
In the gaim-0.11.0pre2-1 that I have installed here it doesn't do this anymore.