KnokiiSync requires:

KDE 3.1 correctly installed. (MANDATORY!)
This of course, means that you will need QT 3.1.x (MANDATORY)
Libgnokii, as provided by Gnokii 0.5.0. (MANDATORY!)
pkg-config >= 0.15.0, which can be found here (MANDATORY!)

You must have a .gnokiirc file propeprly installed in your home directory, otherwise the libgnokii subsystem will not be able to connect to your phone! Before trying to install KnokiiSync, try "gnokii --identify" in the command line. If that works, then try using xgnokii to play around with the contacts. If that also works, then give KnokiiSync a try.