Remember Me fails to parse cookie in Ruby 2.0

I didn't find anything about this googling so it is possible (likely?) that I'm missing something, but the remember_me feature fails for me in Ruby 2.0.

The root problem is that the expiration is stored in the cookie by to_s'ing the expire time, and then read back with Time.parse. But in the USA locales, Time.parse can't properly parse a M/D/Y date format, so once the cookie is set, all page loads begin failing.

I have patched my local copy to work around this by storing the time in the cookie in a more standardized/non-locale-dependent format.

Input welcome.