title: Problem with sending DTMF tones from android app over an active call
body: <p>The DTMF tones are getting generated on my Experia 10 [Android 2.1]. The problem is, I was expecting this kind of behavior :- 
  I call a number, and the call is accepted at the other end. Then I run my application, and I generate DTMF tones from the app. and the same tones should be received at the other end of the call. 
  But this is not happening. I want to know a way, using which I can send DTMF signals over to the other end through a normal phone call. Is there a way to intercept an outgoing call and generate DTMF in between that call ? Please help ! Got stuck with this !
  Thank you in advance !</p>