Hello,
i have elecfreaks gsm shield http://www.elecfreaks.com/wiki/index.php?title=EFCom_GPRS/GSM_Shield and I use this library https://code.google.com/p/gsm-shield-arduino/downloads/list .
SendDTMF work fine, but DetDTMF haven’t response.
Both functions are on the bottom this file https://code.google.com/p/gsm-shield-arduino/source/browse/branches/GSMSHIELD/call.cpp
Other things work fine.
Thanks for your reply.