Most likely the problem is the Motorola. I notice it does have UPnP abilities. See Port Forwarding for the Motorola VT2442 but only as a reference. Don't follow their directions just yet. Log into the motorola as suggested half-way down the page. Then click Advanced tab & top, then the UPnP tab at the left-top side. Make sure it is enabled. Tell me if it already was or was not when you accessed the UPnP settings section.
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