Like this poster in February "I have just connected to Orcon using their Siemens SX763 "Home Hub" modem/router. The only issue I have is that I cannot get Apple iChat to work, which I think is a function of port forwarding on the router. Has anyone successfully set up iChat using this router?" (Darryn) I can iChat other users in New Zealand, except if they are also on Orcon. Anyone else with this problem? Anyone know how to fix it?
UPnP is under Basic Settings>Internet Connection on mine, but yes, it was on.
I already forwarded the ports, it did nothing, but I will try again. (So did the recipient I was trying to communicate with).
try turning firewall and other security features off on the modem.
iChat uses non-standard packets over SIP protocol. If the modem's firewall is enabled it will drop those packets, because they don't comply with SIP spec.
This may help: http://discussions.apple.com/thread.jspa?messageID=2736128
Since my last post on this matter, I have had little success with the SX763 and iChat. Likewise, I was using "Back To My Mac" with my previous ISP quite happily using a Linksys router. Since moving and Orcon, I have not been able to get iChat or BTMM working. I have sought assistance from the Orcon help desk with no joy, apart from a link to a port forwarding website that offered some settings to try and get things going. One email from Orcon mentioned that uPNP was known to have issues and perhaps a future firmware update from Siemens may solve the problem.
In the meantime, I am going to try a different router (I gave my old Linksys away, silly me) and will see how that goes. Apart from the SX763 having a few question marks, I must say I am happy with Orcon - will just have to send them back the home hub.