Unfortunately I did not make following tests early enough to report the findings before ACR 4.3 has been closed, but I hoped that Adobe made some better effort in the meantime to accomodate this camera. Anyway, there is always a next version.
The issue is the White Level setting. I see this explicitely in the DNG files, and the processing of the originating raw files with ACR reinforces the findings:
the white level/clipping point settings are TOTALLY off.
The currect setting is 13600,
at all ISOs.
The actual clipping points are, roughly:
ISO 100: 13824, 125: 16383, 160: 12745
ISO 200: 16224, 250: 16383, 320: 12743
ISO 400: 16224, 500: 16383, 640: 12742
ISO 800: 16223, 1000: 16383, 1250: 12743
ISO 1600: 16224
ISO 3200: 16383
A more detailed report can be seen at http://forums.dpreview.com/forums/read.asp?forum=1019&message=25645921, although those details are rather of technical interest, not necessarily involved in the raw image processing considerations.