Like last time another issue was a bz2 not being available even though on the system it was.
yum bzip2-devel
wget http://python.org/ftp/python/2.7.2/Python-2.7.2.tgz
tar -zxvf Python-2.7.2.tgz
cd Python-2.7.2/
Then configure python to be built absolute path of the virtualenv:
./configure --prefix=/var/lib/jenkins/.virtualenvs/clients/
make
make install