The problem I experience is when I'm standing in the project page and click the
coverage report link I get a 404 - page can't be found. I see in the url that
Hudson is trying to open the link
...host/job/MyProject/lastStableBuild/cobertura/, but at the moment I do not
have a stable build.

However it works if I go to my last successful build and then click the coverage
report link.

Discussed on :
http://www.nabble.com/Problem-with-cobertura-plugin-when-there-exist-no-stable-builds-to14597532.html