2.0.0.beta.19 -"its" construct doesn't work

I have updated RSpec to 2.0.0.beta.19 and “its” construct that has
been working with 2.0.0.beta.18 doesn’t work any more.

Error message is:
implicit argument passing of super from method defined by
define_method() is not supported. Specify all arguments explicitly.

What is the new syntax?

Thank you in advance.