ooh323 does not support h245alphanumerica dtmf mode

I have been trying to use H.323 to trunk Asterisk 1.6.0.9 to Altigen PBX. Everything works fine now, except the DTMF transfer issue. The DTMF mode Altigen uses is h245alphanumerica, I made the changes in the ooh323.conf accordinly. But it just can not work. From the wireshark, I can not the ‘H.245 user input’ tranferred to Asterisk from Alitigen.

I am using asterisk16-addons-ooh323-1.6.0.2-3, and following in my ooh323.conf file. Any insights would be appreciated.

[general]
bindaddr=0.0.0.0
h245tunneling=yes
faststart=yes
gatekeeper = DISABLED

;The codecs to be used for all clients.Only ulaw and gsm supported as of now.
;Default - ulaw
; ONLY ulaw, gsm, g729 and g7231 supported as of now
disallow=all
allow=ulaw
;allow=g723
;allow=g729

context=from-internal
;dtmfmode=q931keypad
;dtmfmode=h245signal
dtmfmode=h245alphanumeric
;dtmfmode=rfc2833

[altigen]
type=peer
ip=192.168.1.25
port=1720