Change Site Server IP Address

Recently, we have had to replace our 2003 site servers with 2008 R2 site servers to upgrade to winpe 4.  When the 2008 server was built, it was using DHCP and then we used the static IP from the old server once the old server was decommissioned.  Once we changed the IP I chnaged the IP listed in the C:\Altiris\Altiris Agent\Agents\Deployment\Task Handler\SBS\initialPXEConfigPath.txt file.  Every so often something is changing the IP addresses in this file back to the original IP the server had.  I need to know what is writing to this file.  Is there a HowTo or whatever, for changing the IP address of a site server?