Issues with g729 and Voicemail

Please see below email that I send to Digium but I have not recieved an answer to yet:

Hi,

I am having a problem using g729 with asterisk@home. I bought 5 licenses for the codec from your website (order 14xxx) and I can make calls fine but when I try to call my mailbox or try to record a greeting I cannot hear anything from the other side. My Asterisk CLI says that I am connected but if I dial *77 to record I hear no beep but a file is saved. When I dial *99 I hear nothing but a file is playing. When I do a “show g729” from the CLI when a call to the mailbox is active I get “0/1 encoders/decoders of 5 licensed channels are currently in use.”

Can you tell me what I am doing wrong or what might be the problem?

Regards,

I have in my voicemail.conf:

[general]
format=g729
maxsilence=0

I can make calls using g729 through my VoIP provider to PSTN phones no problem.

Can anyone help me with this please?