[Serusers] Problems with DTMF using SER and Asterisk

[Anders Hansson]

Hi all,
I have a problem getting dtmf tones throgh to PSTN when using asterisk.
The connections is
SIP phone - Asterisk - SER - Cisco GW - PSTN

When dialling PSTN numbers from the SIP phone and pressing the * or # 
button nothing is happening.
I' ve set the dtmfmode=rfc2833 in asterisk.

The problem is that to be able to control the asterisk voicemail the 
dtmfmode has to be =rfc2833,
and the I can control the voicemail.
But when calling external to PSTN the * and # button is not working.

I do also have another problem, and that is when connecting a ATA box to 
the Asterisk.
If I set dtmfmode=inband, voicemail in asterisk can be controlled but 
not the calls to external PSTN numbers.
If I set dtmfmode=rfc2833, voicemail in asterisk do not work, but 
external calls to PSTN can be controlled with * and #.

What can be the error?
Please help,
Thanks Anders