asterisk users - Jul 2006 - How to collect Call duration, Dialout Call files?

Hi all,

I've been planing to implement a  webcall portal to dial SIP
extensions from my pbx, I've implemented this with dialout call files.

Could you advice me on the best way to collect call duration of this
calls, only this way i can allow my users to place external outgoing
calls.

I've need to use local_chan to avoid CDR missing details. But this way
i get CDR of two calls, and what I wanna get is the call duration of
the bridged call. By default i get 2 calls in CDR, instead of the
bridged final call.

Is it much better to use Asterisk Manager API instead of Dialout Call files?

Marco Mouta