# File lib/action_mailer/vendor/tmail-1.2.3/tmail/mailbox.rb, line 461
    def check_tmp
      old = Time.now.to_i - TOO_OLD
      
      each_filename(@tmp) do |full, fname|
        if FileTest.file? full and
           File.stat(full).mtime.to_i < old
          File.unlink full
        end
      end
    end