yum completely freezes as root

[Ken Schutte]

Hi,

I've got a fresh F7 install, and yum was working fine for awhile, but 
now is *completely* freezing anytime its run as root.  I have to kill 
any yum jobs with "kill -s KILL".

I've notice things work when run from my user account, such as:
$ yum search foo
However, everything run as root freezes,
$ su
# yum

ie even 'yum' with no args freezes!  There is no output, but just hangs. 
  Any ideas?

thanks,
Ken