digi portserver for xenserver

I am trying to install a digi port server on RHEL3 that is running on VM using xenserver. RHEL3 boots using a kernel supplied by Citrix (makers of xenserver). Apparently this type of setup doesn’t allow for compiling kernel modules, like dgrp, outside of the kernel build. Somehow needs to be incorperated into Xenserver using the DDK supplied by Citrix. Does anyone have any experience with this type of setup?

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