nokia and symmetricNAT
 

I know for a fact that symmetric nat would break use of stun in general, whereas nokia firmware has only tackled mobile wifi via stun server. Now would someone please tell me if this actually has rendered usage of wifi phones impractical out there? Does truphone bypass this kind of problem thru use of outbound proxy? My next question is: does outbound proxy solve the issues of wifi phone behind [i]all[i] kind of NAT routers? If so, why do we need stun server in the first place? Why so many complain about lack of firmware update to include stun ability in these nokia phones? Isn't outbound proxy a much better and general solution?

I agree but most of the issues have been with Incoming Calls when it comes to the need for STUN (people can make but not receive calls)

I also feel (without any strong proof) that services like VoXalot and MySipSwitch which employ a wider array of methods to place calls on a case by case basis (eg. ReInvites) seem to have more trouble with the limited setup available on VoIP enabled cell phones... (best way to put it: in being able to merge so many services together, it also seems that these providers rarely have control of the call in its entirety unlike TruPhone which is strictly providing their service, through their servers using their terminating providers)