The issue has been reported on bugs[1] and later fixed[2]. The upgrade procedure works fine for me by now.
[1] http://marc.info/?l=openbsd-bugs&m=147402962517273&w=2 [2] http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/distrib/miniroot/install.sub
The issue has been reported on bugs[1] and later fixed[2]. The upgrade procedure works fine for me by now.
[1] http://marc.info/?l=openbsd-bugs&m=147402962517273&w=2 [2] http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/distrib/miniroot/install.sub