# File lib/action_mailer/vendor/tmail-1.2.3/tmail/interface.rb, line 1010
    def destinations( default = nil )
      ret = []
      %w( to cc bcc ).each do |nm|
        if h = @header[nm]
          h.addrs.each {|i| ret.push i.address }
        end
      end
      ret.empty? ? default : ret
    end