I have a black Hexar AF and I recently found a new-in-the-box Nikon SB-30 flash. However, my Hexar AF doesn't seem to have the firmware upgraded because I cannot use the manual GN selection described above by pvdhaar (and found on Johan's web site as well). I assume the Hexar firmware upgrade is no more possible.
So no P-mode flashmatic for me unfortunately. But I think I still can use my SB-30 in Hexar's M-mode like any normal auto-thyristor flash. I just set the aperture in the camera and in the flash to be the same and shoot away. In case I need a fill flash I just trick the SB-30 to give out a bit less juice by setting it to one or two stops larger aperture (like f/8 -to- f/5.6) than in my camera. I will take a test roll or two later with SB-30 flash and Hexar but I just want to make sure I'm on the right track here.
Of course I could just buy a Konica HX-14 or -18 flash but I think the SB-30 looks kind of nice on the Hexar.