Voice SMS Service on PSTN and Mobile Network of MTNL,Delhi:
 
Procedure for using  this service: 

 I     Composing a message: 
 1.   Mobile to Mobile & Landline to Mobile:
      Dial 1* followed by recipient number.
 2   Landline to Landline.   
      Dial 1* followed by recipient number
 3.   Mobile to Landline 
       Dial 1* followed by recipient phone number along with STD Code i.e. 011 
 II   Retrieve new messages (For Landline & Mobile)
     Dial 1*0* to listen to all new messages.   
 III. Retrieve old messages (for Landline & Mobile):
      Dial 1*1* to listen to all old messages.  

In case of Mobile customer, notification will appear that a new voice SMS message has  been received from a number.  In case of PSTN line, only ringing will go to the customer and on lifting the PSTN line, he will be able to hear the voice message.  There are various options also available to customer like “ forwarding, deleting, reply, storing” etc. Presently this service will not be available to CDMA customers and Mobile customers in NCR town.

For detail commercial conditions click here