I have good news to our Windows users. The new installer (0.6.4-4-dev) of Smuxi now supports Windows 64-bit. This was tested on Windows Vista and Windows 7 RC1. Smuxi is not running in 64-bit execution mode (yet) but in 32-bit mode because GTK+ is not yet fully ported for Windows 64-bit. Windows XP 64-bit should also work, if not please write me an email or join our IRC channel. You can get Smuxi 0.6.4-4-dev from the download page.