freebsd-update and boot environments clash - rm / attempted!

[Arthur Chance]

I just updated my systems to deal with the latest security bulletin. On 
the machines where I'm running zfs based boot environments I got the 
somewhat worrying:


root at arthur:5# freebsd-update fetch install
Looking up update.FreeBSD.org mirrors... 5 mirrors found.
Fetching metadata signature for 10.1-RELEASE from update4.freebsd.org... 
done.
Fetching metadata index... done.
Fetching 2 metadata patches.. done.
Applying metadata patches... done.
Inspecting system... done.
Preparing to download files... done.
Fetching 8 patches..... done.
Applying patches... done.
Fetching 14 files... done.

The following files will be removed as part of updating to 10.1-RELEASE-p2:
/

The following files will be updated as part of updating to 10.1-RELEASE-p2:
[list snipped]
Installing updates...rmdir: ///: Is a directory
  done.

Fortunately it didn't remove /, although I really don't understand that 
message.


-- 
Those who do not learn from computing history are doomed to
GOTO 1