Ok, now I've autoconfiscated octave-gui and you should be able to build it. If you have QT4.1 problems though, you're going to have to sort those out... :-/ Over here, everything compiles and the mainwindow comes up so it's now at the same state as it was pre-autoconfiscation (octave still doesn't init right.)
I strongly advise everyone but David to stay away from this.
Building is standard, but it's in maintainer mode. Here's what I do.
1) Fire up an appropriate shell. I've got "shell.bat" and "shell-x64.bat" (for Windows XP x64) in that directory for that purpose. It's basically the setup from your
octave.bat, then it starts sh.exe from mingw.
After a 5 second pause (or so), a window will pop up.
I haven't tested, but I don't think stdout/stderr work. So if you're going to debug, you have to use some other way. To help you out, I've declared the following global variable:
string david_output;
If you stick anything in there, it'll appear in the mainwindow when the mainwindow first appears. Otherwise I think you can open files and stuff. Right now, as an example, it prints the return code of octave_main, which is 1.