How to get alerts when non domain computers get an IP from windows 2008 R2 using SCOM 2007 R2

Before upgrading from windows 2003 R to 2008 R2 (using new servers)

Our System Centre Operations Manager used to alert us to any PC which were not part of the our network i.e. non domain member getting an IP address. It used to show the machine name and IP address of the computer.

The DHCP were running on the domain controller on the 2003 R2 system they are now running on the 2008 R2 domain controllers.

Does anyone know how this was done or can be done?

Thanks

Shana

Thanks, Shana