[HELP]rtp.c:565 ast_rtp_read: unknown rtp codec 101 received

Hi all

I just install Asterisk 1.2.4 in freebsd, before that, i use 1.2.3 and everything work well. but after upgrade, only
caller can send DTMF correctly, and if press any key on called phone, the error "rtp.c:565 ast_rtp_read: unknown rtp codec 101 received"
will show in alsterisk.

Anyone know how to solve this problem?
Thanks a lot.