what's wrong with this funky errors running Shoulda tests

I have a ruby project that passes all tests with 'rake test' (which loads test/**/*_test.rb). I created a Shoulda unit test debug target loading the same files. But it keeps complaining errors running some (but not all tests under test/functional) The errors produced (without any stack trace anywhere)

NoMethodError: undefined method `kind_of?=' for #<MyClassName:0x10b32ec20>
test/functional/my_test.rb:48:in `__bind_1315359581_241280'

This line does the same Factory Girld creation like many other lines before it

      @obj2 = Factory.create(:obj2_id)

I even copied a working test from the test/unit/ folder over to test/functional and it fails too. (but again not all tests over there fail.)

OS: MacOS X, RubyMine: 3.2.3/4

Any idea what I'm running into?

Thanks