[rspec-users] Rake spec failure in beta.13

[geetarista]

I just upgraded to beta.13 and I'm running into an issue where when I
run 'rake spec', I get an 'uninitialized constant Comment' error.
Comment is the first model (alphabetically) in my project.  If I
switch back to beta.12, it works.  If I use 'spec .' and not 'rake
spec', it also works.

Environment: Rails master, Mongoid master.