asterisk users - Mar 2011 - Ignoring RTP 2833 Event: 0000009f. Not a DTMF Digit.

Hello !

My asterisk log is full of messages like this:


[2011-03-06 19:01:15] DEBUG[20556] res_rtp_asterisk.c: Ignoring RTP
2833 Event: 0000009f. Not a DTMF Digit.
[2011-03-06 19:01:20] DEBUG[20556] res_rtp_asterisk.c: Ignoring RTP
2833 Event: 0000009f. Not a DTMF Digit.
[2011-03-06 19:01:25] DEBUG[20556] res_rtp_asterisk.c: Ignoring RTP
2833 Event: 0000009f. Not a DTMF Digit.
[2011-03-06 19:01:30] DEBUG[20556] res_rtp_asterisk.c: Ignoring RTP
2833 Event: 0000009f. Not a DTMF Digit.
[2011-03-06 19:01:35] DEBUG[20556] res_rtp_asterisk.c: Ignoring RTP
2833 Event: 0000009f. Not a DTMF Digit.


This happens for different clients..

Any ideas what would that mean and how to fight it?


Thanks,
Nick