Just found this posting on the SCE forums regarding integration of SCE and FCS:
http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=1797488&SiteID=17 is the link, The text is below from the forum posting:
Question 16: Can I use Essentials 2007 and Forefront Client Security to manage the same computers?
Yes. Please read through these configuration steps to understand how to use both products in the same environment.
· Essentials 2007 must be installed on x86 hardware.
· Forefront Client Security must be installed in the 2 machine (or more) supported configuration from their guide, where the SCE server is the distribution server component. No other FCS workload is supported on the Essentials server.
· All FCS managed machines must be SCE managed machines
· If the FCS distribution server is installed on to Essentials 2007, it will alter the subscription and approval settings already configured. The administrator will need to re-run the Update Management Wizard again to apply custom settings. It is important that the “Definitions” classification and the “Forefront” product remain subscribed and declared in the auto-approval settings.
· If Essentials is installed on to the Distribution server running FCS, the same classification and product settings need to be applied.
· The Essentials 2007 default client and server scan times fall 1-2 hours after the FCS scan, which may leave managed machines up to 22 hours stale. We recommend using Group Policy to set the client scan time to 4:00 AM, and the Server Sync time to 1:00AM.
It is important to note that the purchased limits of the FCS solution must remain within the purchased limits of the Essentials solution.