Silencing Mock

[夜神 岩男]

I've never really payed attention (or cared) until now, but Mock is 
annoying me with copious lines of:

...
DEBUG: warning: group iwao does not exist - using root
DEBUG: warning: user iwao does not exist - using root
...

during builds. I asked the search gods about this one, and all I find 
are tons of log files scattered around the net with the same messages in 
them -- but nobody asking if this is an error or not.

The builds work fine, its just annoying -- but on systems where this 
error pops up the command "mock --scrub=all" can't be run, and I feel 
the two are probably related.

Any ideas? I've got to be missing something small here.