[CentOS] recommended way to install source rpms?

Mon Oct 11 13:53:45 UTC 2010
Patrick Lists <centos-list at puzzled.xs4all.nl>

On 10/11/2010 07:10 AM, Mathieu Baudier wrote:
> - install 'mock' (IMPORTANT: install the one from CentOS, exclude the
> one from EPEL in your repo file)

Would you mind giving a hint why one should not use mock from EPEL? 
Afaict the mock version in the CentOS repo is 0.6.13 which was released 
years ago and the one in EPEL is 1.0.7 which is current.