Problem is in reiserfsprogs?
thanx for the answer.
It seems there is a bug in the latest reiserfsprogs or it is incompatible with the filesystem on the disk
I tried to use older version of Knoppix (4) with reiserfsprogs-3.6.19-1 and it works now - no segfault, mount successfull
However the filesystem seems to be dead - I can see files, but except few all of them are full of thrash ... well, this is how the data can end ...