I forgot to mention this: the GUI must run on Windows (2000,XP,2003), Solaris, HPUX and in near future on Linux.

So, from this point, Gtk is not a very good choice (it's hard to compile and run from a CD/DVD on Windows)

Wx and Prima looks nice, I'll give them a try

Some issues that I'm afraid of (because I get them in TK) are:

• GUI that froze during procesing databases in the background - in Java the process can be launched on a separate thread (I know that this can be solved using threads in perl, but I'm not sure how well it's working on Windows).
• Tree view of file system (like Tk::DirTree that is buggy)