You can try sw on the list above (I do not remember which ones support ProBack, nor tried all), but so far got best results with CS2 calibrated with Thomas Fors -script.
Another option would be to convert to DNG first (with Adobes free converter - would also add some futureproof opening facilities and xml/metadata/archiving benefits), and then open to sw supporting DNG.
http://www.cybercom.net/~dcoffin/dcraw/
regards lasse s