I’ve bought hardphones from two different chinese brands.
I don’t know why they only work with the SIP INFO DTMF option, even though they also have the RFC2833 option.
I’ve tried with softphones, and they work perfectly with the RFC2833.
I am using Asterisk at Home 2.6 with Asterisk 1.2.6
I would like to know if somebody had a similar problem
Oh…i am sorry to hear that !