Pending test cases throw an exception in the browser runner

[aron]

The following example from the documentation throws an exception:

describe('Array', function(){
  describe('#indexOf()', function(){
    it('should return -1 when the value is not present')
  })
})

Exception thrown:

Uncaught TypeError: Cannot read property 'stack' of undefined in mocha.js:815

See example: http://jsfiddle.net/vxGgv/embedded/result/

Tested in Firefox 7.0.1, Safari 5.1.1 & latest Chrome beta.