Description of problem:
When building something against the newly provided packages by redhat postgresql84-devel using mock, it's BuildRequires appear to be mucked up.

Everything builds... but during the mock clean up, the rpm fails to gracefully uninstall itself with the error (taken from verbose output of mock):
DEBUG: + postgresql84-devel-8.4.7-1.el5_6.1
DEBUG: /var/tmp/rpm-tmp.59300: line 27: postgresql84-devel-8.4.7-1.el5_6.1: command not found
DEBUG: error: Bad exit status from /var/tmp/rpm-tmp.59300 (%clean)
DEBUG: RPM build errors:
DEBUG:     Bad exit status from /var/tmp/rpm-tmp.59300 (%clean)
DEBUG: Child returncode was: 1
INFO: EXCEPTION: Command failed. See logs for output.


Version-Release number of selected component (if applicable):
8.4.7-1 (the one shipped with RH57-beta)

How reproducible:
just build with it in a mock environment.  In the above example I was building against a third-party (redhat-unsupported) app libpqxx.

Steps to Reproduce:
1. create a very minimial source rpm to be built that BuildRequires postgresql84-devel
2. attempt to build your package through mock
3. assuming your source is okay, mock should fail to preform the cleanup of the postgresql84-devel package and exit
  
Expected results:
mock would gracefully preform the removal of rpm and then finish by having the built content appearing in the mock 'results' directory.

Additional info:
Since everything builds okay, it's no sweat to fetch the rpms from /var/lib/mock/<mock env root>/builddir.

I set the ticket to use x86_64 hardware, but this issue also occurs with i386 as well using mock.  I have not tested the other architectures.