FreeRDP/FreeRDP — pull request #1740 by bmiklautz (2014-03-14 21:02:05+00:00)
Title: only process msg channel pdu if msg channel is set

In case there is no message channel messageChannelId is 0. In this case it can happen that channels with (invalid) id 0 are processed by rdp_recv_message_channel_pdu instead of the regular path where unknown/invalid channels are handled.