I am using TDD to write my game logic, using Unity's packaged version of MonoDevelop. I can add the nunit.framework assembly to do regular unit tests, but I would also like to use mock objects. It looks like MonoDevelop is not packaged with the nunit.mocks assembly. Is there a way to make this work?

I did try installing NUnit on my workstation and then referencing the assemblies from there, and that worked for a while. Then, the tests failed to load, and I could not get any error message to help me track down the problem. Since I had not been using mocks yet, I just reverted to using MonoDevelop's packaged nunit assemblies.