ls on ZFS showing unexpected directory content

Hi,

Situation:
- shell is bash
- Root container mounted on zroot
- extra container mounted on /extracontainer, on USB drive which spins
  down on idle
- cd /extracontainer
- cd subdir (takes a while, as drive has to spin up - getting bored,
  hitting CTRL-C)
- prompt still shows /extracontainer, but `ls` now shows content of
  /extracontainer/subdir
- cd .. && cd extracontainer
- Now `ls` shows content of /extracontainer

Expected behavior?

Thanks
Michael

-- 
Michael Gmelin