rails3b3 tests: tons of warnings

Hello everybody, I've just tried to run the test suite of rails 3 beta
3 but I get a lot of warnings: http://gist.github.com/367000

This is my `rvm info`: http://gist.github.com/367001

Note that this is a fresh installation of rvm, ruby 1.9.2-head and
rails 3b3 (subsequent to a "rvm implode").

I suppose this is related to:

Does this behavior modifies in some way the results of the tests?