I've compiled HTk for ghc-5.04.2 on Solaris, Linux and Windows, and put binary bundles at http://www.informatik.uni-bremen.de/htk/ So you can write portable graphical user interfaces using the latest release of your favorite Haskell compiler. Sorry it's a bit late; it's not that it's difficult, it's just that I am a shortage of manpower. I hope I produce binaries for ghc-5.04.3 a bit faster.