As I mentioned in my post yesterday, not being able to support scrollback with the client was a problem in the wxWidgets-based version. This is because it used the Simple DirectMedia Layer (SDL) for the text rendering, and that just has a 2-D panel that text can be rendered to. Adding scrollback to that kind of system would be a large amount of effort.
Since the original development on the client was started back in 2005, wxWidgets has added the wxRichTextCtrl control, which lets you create rich text box — as in, a text box that has color, images, and all sorts of happy goodness like that.
I spent some time ripping out all of the SDL portions of the client and replacing them with the rich text control. The end result is that it does everything it did before, but has scrollback, uses less CPU, and has less memory copying going on (which means fewer possible points of failure). It still needs some tuning, but it already uses five fewer code files than the previous attempt.