Sorry to hijack like this, but i had the same problem with my E7. It wont charge using iphone power adapter. Reason i want to use it is because i've replaced the usb connector inside my E7 and it seems it only charges with usb-PC cable, so i want to use that with my phone. And only way i can connect to mains is by using this adapter.
I took the adapter open and noticed it had the data+/- bridged and had voltage going to them through a resistor. I tried removing the resistor so data lines are bridged but still no go.. I tried unbridging them but still wouldn't work.
Does the E7 need different pinout for making it work with a charger?
I have a converter that works in a car socket, and that works fine with this cable. I measured the pins on that, and it seems to get about 2.7volts on the data pins, so maybe i need to connect lower voltage for data pins?
Thanks for any help..