Cisco Firewall :: IP Phone 7961 - Inspection Rule Activated And Call Works

I got a problem yesterday with a customer that says that the calls from a CISCO IP Phone 7961 to an Alcatel 4018 IP Touch didn't work, well the phone rings but there's no voice; I manage a CISCO ASA version 8.2(1) and I was checking the Inspection Rules in the Service Policy Rules section and when you open the inspection_default at the Rule Actions tab I find that the H.323 H.225 and H.323 RAS box wasn't checked so I ask to the customer to made a test and the same problem happen so I checked both box and again ask to the customer for a test and it works.
 
I was talking to a partner and he said that maybe this Inspect fix some signaling parameters of this protocol that can't work fine behind of a firewall.