The version tagged as "port-1.0" on gitorious.org/kbarcode-kde4 works and has the most of the Kbarcode's functionality except a database support. It compiles succesfully with few compile warnings and uses all of the Kbarcode's source files except gnubarkodeengine.cpp and gnubarkodeengine.h . But it still uses QT3 support classes like Q3Canvas, Q3SqlCursor, Q3DataTable, Q3SimpleRichText, etc. I am currently working on porting the QT3 support classes to pure QT4. I have already ported Q3Canvas and related stuff to QGraphicsScene (which proved to be the most difficult porting) but I haven't pushed it to the online repository on gitorious.org/kbarcode-kde4 yet.
I am so glad to this project to be continued! It looks much prettier than the KDE3 version and even did import my old KBarcode3 label files without any problems.
Want some screenshots? Here you got.