I also have problems with softdep enabled

  panic: initiate_write_inodeblock

and also

  panic in softdep_setup_freeblocks, called from ffs_truncate.

  (this in single user running 'ktrace foo' after 'ktrace fo' which was
  a typo, and the ktrace.out was in a softdep filesystem)

Without softdeps the machine seems to run ok.

This was a on a 1999-vintage Thinkpad 600E - decidedly a single
processor machine, for what that's worth.