[Asterisk-Users] Asterisk missing DTMF tones from some cell phones

[Bryce Nesbitt (mailing list account)]

While most cell phones are fine, some cell phones don't seem to produce 
DTMF digits that Asterisk/Zapata will detect.  One of our salespeople 
has an AT&T model that never gets any digits through.

Is there a known solution?

I understand, of course, that with cell phones the DTMF tones are 
actually created at the base, and that pressing the key longer usually 
does not result in longer tones.

I have seen 
http://lists.digium.com/pipermail/asterisk-users/2004-February/037319.html

             -Bryce

PS: I'm actually using the http://www.mipl.org browser, which does
    zap_getdtmf(zap,1,NULL,0,0,0,ZAP_HOOKEXIT), etc.