Nokia PPH1(2.5 jack 4-pole+charger combined plug) to Popport

[mateusz]

Has anyone tried to convert the old Nokia mini-car kit PPH-1 (with a 2.5mm 4-pole jack):

to pop-port?
BTW there is no buttons, or built in microphone in the PPH-1...

The charger pins are 1 and 2 from the pop-port are easy to find in the PPH-1. The rest is bit more tricky. There are five wires other than the red-black 6v Vin and GND (why 5 - it is a 4-pole connector! - oh, I got it there is a yellow cable going straight from the ext mike socket in the PPH-1 to the GND in the charger plug going into the phone)

Should ACI be connected somewhere?
Should I short pins 12 and 14 (and 11 13) to convert to mono?
Where should the shield GND be connected?
Is there anything else I should worry about?
Mateusz[/url]