In my projects that has never had a stable build, the "Coverage report" link on
the project summary page gives a 404. Same problem for the link in the menu on
the left.
However if I click on the last build (unstable, but successful)and from the
build summary page the coverage report link works and gives me the expected
information.

Further I get no graphing of the coverage trend either.

I am certain everything is set up correctly as it works if I drill down into a
specific build. I believe this is a bug in the way cobertura generates those
links, as it seem to expect a stable build, when it should in fact point to the
lastSuccessful build.