I tried the troubleshooting steps in the sticky post regarding this issue however when I go to the port forwarding site, it tells me I need a static IP address to use with my AirPort Extreme router. The site offers a download that is supposed to set up the static address for you but when I download it and then open the program, the text is all symbols and it states on the top of the window that the program can't run in DOS mode. So, since I couldn't run that program I followed the second, and only other option, which is to set up the static IP address manually. The instructions for this are very clear however, it is outdated and is for software version 10.4. I am running 10.6, snow leopard, and some of the steps just don't apply or won't work with newer operating systems. I tried to follow the steps and fill in the blanks but all I ended up doing was messing up my whole network and causing myself to have to restore and set the whole thing back up again. My router does support the NAT and I also checked the auto-configure box. Since none of that worked I followed the support instructions on this site and forwarded the proper ports. After all of this I still cannot connect via 3G. Any help would be greatly appreciated...thanks!