Confirmed - Dension Gateway iPhone 3G Charging (UPDATED 08/03/09)
I finally got a chance to test out the information I received as far as the ability of the Dension Gateway 300 and 500 products to charge the iPhone 3G by using the already-existing dock connector cable that has a blue end, and I can happily confirm that this is indeed the case. Over time, Dension has supplied three connector colors - grey, green and blue. I tested all three, and only the blue cable will charge the iPhone 3G properly on the Gateway 300 and 500. I also was able to test this functionality through the Dension BT1000 Bluetooth unit, and can confirm that this works properly as well.
You still get the “This accessory not made to work with iPhone” message about GSM noise (see posts below), but there is no mention of charging issues via the iPhone 3G itself.
Update 08/03/09:
Dension recently released an entirely new cable with a white end that replaces the grey, green and blue-end cables mentioned above. All their current products ship with this cable, and it is the new standard for compatibility with all iPods and iPhones, including the iPhone 3GS.
Pictured below is the new white-ended cable.