What's this mounted temporary drectory? /tmp/autoKVio9R

[furufuru@ccsr.u-tokyo.ac.jp (Ryo Furue)]

Hello all,

I recently found the following:
  $ df -k
  [...]
  /tmp/autol8wP90       37483560   2742148  32837312   8% /tmp/autoKVio9R
  $
which I'd never seen before.  I'm the sole user and the admin of the machine.
Also,
  $ ls -lF /tmp
  total 28
  drwx------    0 root     root            0 Jul 17 20:21 autoKVio9R/
  [...]

and there's no /tmp/autol8wP90 .

I don't remember what I did diffrently recently, but I certainly didn't
create the directory or mount it.  I wonder if somebody could guess what
it is. Is it something dangerous? like a symptom of being cracked?  I use
Debian 3.0r2.

Thank you,
Ryo