Allow the following ports/protocols on the Actiontec "Advanced Filtering" page under the "Output Rule Set" under the heading "Broadband Connection (Ethernet) Rules"
Accept (using SPI) the following for outbound connections worked for me:
TCP Any -> 49207
TCP Any -> 554
UDP 21310 -> Any
Note that there are certainly other ways to accomplish this, but it is important to note that NO INBOUND ports need to be opened, meaning opening outbound (even fairly relaxed rules) for these ports should work.
I tested this several times on my boxes, but your mileage may vary.
Written by Bruce Thomson -
Last updated on 07.24.07