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 == linux-fdisk wiriting things behind MBR == 

 Right now i suspect fdisk (util-linux 2.20.1) writing stuff behind the MBR (but not necessarily after the beginning of the first partition). I'm sure this happend while i only changed the partition type from 7 to 83, while bootflag set(unchanged). Manpage only says fdsik ""does fuzzy things"" (and strangely recommends not to use itself ..).   "