Description of problem:
Jobs on RHEL6 / ComputeNode fail, because of external watchdog expiration. Searching in installation logs, there are missing dependencies when installing the beah package:

program.log:
...
22:57:52,552 INFO    : Resolving Dependencies
22:57:52,553 INFO    : --> Running transaction check
22:57:52,553 INFO    : ---> Package beah.noarch 0:0.6.26-1.el6 will be installed
22:57:52,583 INFO    : --> Processing Dependency: python-twisted-core for package: beah-0.6.26-1.el6.noarch
22:57:52,586 INFO    : --> Processing Dependency: python-zope-interface for package: beah-0.6.26-1.el6.noarch
22:57:52,587 INFO    : --> Processing Dependency: python-setuptools for package: beah-0.6.26-1.el6.noarch
22:57:52,589 INFO    : --> Processing Dependency: python-twisted-web for package: beah-0.6.26-1.el6.noarch
22:57:52,590 INFO    : --> Running transaction check
22:57:52,590 INFO    : ---> Package beah.noarch 0:0.6.26-1.el6 will be installed
22:57:52,596 INFO    : --> Processing Dependency: python-twisted-core for package: beah-0.6.26-1.el6.noarch
22:57:52,597 INFO    : --> Processing Dependency: python-zope-interface for package: beah-0.6.26-1.el6.noarch
22:57:52,599 INFO    : --> Processing Dependency: python-twisted-web for package: beah-0.6.26-1.el6.noarch
22:57:52,600 INFO    : ---> Package python-setuptools.noarch 0:0.6.10-3.el6 will be installed
22:57:52,874 INFO    : --> Finished Dependency Resolution
22:57:52,892 ERROR   : Error: Package: beah-0.6.26-1.el6.noarch (beaker-harness)
22:57:52,892 ERROR   :            Requires: python-twisted-core
22:57:52,892 INFO    :  You could try using --skip-broken to work around the problem
22:57:52,893 ERROR   : Error: Package: beah-0.6.26-1.el6.noarch (beaker-harness)
22:57:52,893 ERROR   :            Requires: python-twisted-web
22:57:52,893 ERROR   : Error: Package: beah-0.6.26-1.el6.noarch (beaker-harness)
22:57:52,893 ERROR   :            Requires: python-zope-interface
22:57:54,129 INFO    :  You could try running: rpm -Va --nofiles --nodigest
...

This happens only on ComputeNode variant, since ComputeNode doesn't contain following required packages:
python-twisted-core
python-twisted-web
python-zope-interface


Version-Release number of selected component (if applicable):
0.6.11

How reproducible:
always

Steps to Reproduce:
1. run a test on RHEL6/ComputeNode
  
Actual results:
job fails, beah is not installed in %post

Expected results:
all packages, which Beaker needs, are succesfully installed, job doesn't fail because of external watchdog

Additional info:
This issue is blocking automated testing of RHEL6/ComputeNode variant in Beaker