I've downloaded the gui branch of Octave, and tried to compile it with MinGW Qt-4.8.0.
Well, it did compile....But it stopped there.
Well, running the octave-gui.exe gave me a nice messagebox saying:
"The application was unable to start correctly (0x0000007b). Click OK to close the application."
Then I tried to run the qterminal.exe, and this worked...almost...But it didn't give me a prompt....