Description of problem:
Yum produces an error by searching for a package name:

Traceback (most recent call last):
  File "/usr/share/PackageKit/helpers/yum/yumBackend.py", line 391, in _do_search
    for (pkg, inst) in res:
ValueError: too many values to unpack


Version-Release number of selected component (if applicable):
3.2.27

How reproducible:
always since last yum update

Steps to Reproduce:
1. open PackageKit
2. search for package name