upgrading with rpm for CentOS 6.3

[dx k9 <bitsandbytes88@xxxxxxxxxxx>]

Since there is no 9.1.9 rpm for CentOS, I tried running the 'yum install postgresql91-server' .
 
That updated my default version from 8.4.12 to 8.4.13.   But I really need my working version upgraded.

PGENGINE=/usr/pgsql-9.1/bin

Or is there a way to update /etc/yum.repos.d/CentOS-Base.repo, [base] and [updates] sections to make it know that I'm running postgres 9.1.4 and update that location?