Cookie's expiration date is being ignored by Firefox

Rails 2.3 uses dashes instead of spaces when specifying a expiration date (it used spaces at least until 2.1.2) so cookies's expiration dates are completely ignored at least in Firefox and any cookie set through Rails is lost at the end of the session.

Adding insult to injury I shall mention that rails 2.3 removed the ability to test easily test cookie's expiration dates so the only possible way is to hack around the headers.