Mic not working properly in Gtalk & Yahoo Messenger

:( :( :( I have a headphone cum mic i have tested my mic in vista sound recording and it records sound well but when i use it in gtalk or yahoo messenger only headphone works i.e
i can only hear but other person cannot hear what i am saying(mic not working in gtalk).

There are Voice testing feature in Yahoo messenger, are you not able record sound in that too ? Also see volume of MIC.

if it is gtalk have a look at it

ceveni.com/2009/02/microphone-not-working-with-gtalk-and.html