# File lib/sqs/right_sqs_interface.rb, line 262
    def list_grants(queue_url, grantee_email_address=nil, permission = nil)
      req_hash = generate_request('ListGrants', 
                                  'Grantee.EmailAddress' => grantee_email_address,
                                  'Permission'           => permission,
                                  :queue_url             => queue_url)
      response = request_info(req_hash, SqsListGrantsParser.new(:logger => @logger))
        # One user may have up to 3 permission records for every queue.
        # We will join these records to one.
      result = {}    
      response.each do |perm|
        id = perm[:id]
          # create hash for new user if unexisit
        result[id] = {:perms=>[]} unless result[id]
          # fill current grantee params
        result[id][:perms] << perm[:permission]
        result[id][:name] = perm[:name]
      end
      result
    end