I was wondering if anyone can help me.  We  (my company) are having a problem with sending calls to multiple Cisco ATA 186s behind a NAT.  We get one way audio.....we have a company in Iraq that is part business, but also a relief organization.  We need someone to help us get these calls working, so that a doctor from Boston can call into a hospital in Baghdad and work with the doctors there (for example).  We have VoIP and networking people working on it, but there is a problem with the port assignments (not sure of more detail yet).