Shutting down error

[Camaleón <noelamac@gmail.com>]

Hello,

I'm running an updated wheezy and since weeks ago, when shutting down (or 
restarting) the system I can see this message:

[FAIL] Killing all remaining processes... failed.

(here is a snapshot)

http://picpaste.com/shutdown_error-rEoKsztL.png

There are no more errors (I mean, system is running fine), but seeing 
"red" letters with a "failed" word all in one line is a bit scaring. 
Well, what really worries me is the fact the message is consistent (it 
happens at every shutdown/restart) and has not dissapeared yet and I'm 
seeing it since long time... :-)

Anyone seeing this message? If not, how could I debug what is generating 
this?

Greetings,

-- 
Camaleón