Not seeing Tests tab

When we run test:units via Rake with the Test::Unit reporting turned on specifying RVM interpreter jruby-1.6.5.1, we are not seeing a Tests tab and test results. We only have the raw logs to work from when deciphering a build problem.

The agent machine has the test-unit 2.4.5 gem (we've also tried the 2.4.3 gem). I can see the gem listed in the step where we run bundler. Yet, no tests tab.

Any ideas on how to fix or at least isolate the problem would be appreciated.