Rod,
This should work fine with a DL-380, but the server needs to be built with Windows 2000 using the Operating System installation CD that came with the CM3.0(8) CD. Using that OS installation CD will cause the CallManager to recognize that you are using a supported platform.
Also note that you will definitely need to install CM3.0(8) first, then you can install all the appropriate patches and perform an upgrade to CM3.1(1).