BT Homehub 3, Source Connection Error, Port fowarding - HELP?

[kmpowell]

I'll keep it short and sweet:

iMac (running OSX 10.7.4)
BT Homehub 3 (iMac connected directly to it via WiFi)
iCamsource 2.4.4 running on the iMac
2x foscam F18910W's being used wirelessly through the BT Homehub 3
No firewalls, no restictions.

 - The iCam app on my iPhone and iPad will connect fine if I am using the same BT Homehub 3 Wifi network, however when on 3G I get the "Source Connection Error" message. I've read about Port forwarding, however on portforward.com there's no option for the Homehub 3.

- I've tried 'Auto config', and it says "success", but no joy
- I've logged into the HH3 control panel and tried switching off the firewall, but no joy.
- I've logged into the HH3 control panel and made sure UPnP is enabled, but no joy.

I'm a bit stuck as I bought this app purely so I can monitor my dog when I am work. I know my way around most settings, but I'm a bit stumped here and I'm afraid I'm going to do more damage than good if I continue...

Help?  

Thanks in advance.

[kmpowell]

**SOLVED** I finally got it to work!  

For Port Forwarding, I would recommend anybody having trouble to view this step by step guide: http://www.youtube.com/watch?v=xXvkBMqU6P4

After following this to the letter iCam now works a treat over 3G.