[Tomas Kukosa <tomas.kukosa@xxxxxxxxxx>]

> 
> It might be interesting to see what AbiWord:
> 
>         http://www.abisource.com/information/about/
> 
> does.  From the screenshots, it appears to use the native GUI toolkit on
> Windows and BeOS, and it uses GTK+/Gnome on UNIX/X.  The screenshot for
> MacOS X uses GTK+ atop X, but the document shown in that screenshot
> indicates that there's also a version for MacOS that uses Carbon.

The other interesting project might be the wxWindows 
        http://www.wxwindows.org/
It can be used on the following platforms:
 Windows (9x, ME, NT, 2000, XP)
 Unix/GTK+ (GTK+ 1.2.6 or later)
 Unix/Motif (Motif 1.2 or later, Lesstif, OpenMotif)
 MacOS (9.x, X)

There are some other unofficial distributions for OS/2, MGL and
MicroWindows.