COM+ 1.5 and 1.0

Ran into this today. Not horribly noteworthy but it can bite you if you blindly click through the COM+ application export wizard.
http://support.microsoft.com/default.aspx?scid=kb;EN-US;873192
"You receive an "Error registering COM+ application" error message when you install an application proxy in COM+ 1.0"

"The Save application in COM+ 1.0 format – some properties may be lost option on the Application Export Information page must be enabled if you want to export your application proxy for COM+ 1.0. "

Windows XP and Windows Server 2003 run COM+ 1.5 and Windows 2000 runs COM+ 1.0.