asterisk users - Nov 2006 - upgading to install-misdn 0.3.1-rc23 broke dtmf detection on some calls

Hi,
I installed a new PBX to replace my old one with same TDM400 and beronet 
BRI card but different mISDN driver. I upgraded from 0.2.1-rc13 to 
0.3.1-rc23 (both taken from beronet site).
The problem is after upgrade my Asterisk stopped to detect dtmf on some 
calls but the misd.conf file is the same!!!!
Since it worked with previous mISDN version, is there anybody who knows 
where is the problem?

TIA

Giorgio Incantalupo