Microphone convertion help

(this is the same "computer to cellphone headset" topic, but i have refined my problem and re-writen this topic)

is there any circuit to convert a computer microphone to a carbon microphone? a carbon microphone is the cheap, yet effective, kind used in phones, it opperates using a cylinder filled with carbon dust and depending on how much that cylinder is compressed the resistance changes (2 wire mic). a computer microphone uses 3 wires and although i'm not sure how exactly it opperates i know (rather 'think') it needs a ground and two other connections. i'm just wondering if it is posible to convert the signal from a computer mic into one readable by a telephone mic. (need to hook headset upto cordless phone, got headphones working but mic is being a pain) any help would be appreciated. thanks

Yes, possible, but the cordless-phone not contain a carbon mic.In the very old type was dynamic type, but nowadays all contains electret.
The computer mic. is electret, probably stereo (3legs)

ya, i found a site w/ a lot of info on it about electet mics. and it had about 4 ways to hook up that type of mic to things. anyway i finally got it working and now i can use my computer headset w/ my cordless phone.