I did not yet implemented GPG Key.

  [K2 - Perl]
  name=K2 - Perl
  baseurl=http://108.35.22.7:1111/centos/$releasever/perl/$basearch/
  enabled=1
  gpgcheck=0
 
  [K2 - Update]
  name=K2 - Update
  baseurl=http://108.35.22.7:1111/centos/$releasever/updates/$basearch/
  enabled=1
  gpgcheck=0

use following centOS dev wiki

  [c5-testing]
  name=CentOS-5 Testing
  baseurl=http://dev.centos.org/centos/$releasever/testing/$basearch/
  enabled=1
  gpgcheck=1
  gpgkey=http://dev.centos.org/centos/RPM-GPG-KEY-CentOS-testing
  includepkgs=php*

Kickstart