I mentioned here a few months ago that I'd got DECnet-VAX Phase V working under simh using the DUP11.  In the meantime, I've fixed some simh DUP11 bugs and also added DPV11 support, all of which is available in the latest version of open-simh on github.

In the unlikely event that anyone else wants to try this out, I've written a blog post that I hope contains all the relevant information: