The call logs used by the CDR are from the billing (bssxml) server not the accounting server (acctxml).
I really do not like 3Com's call report interface, so what I do, it use it to retrieve the call logs, then go into the app's database (it's an Access database) through the backend and create create my own reports. the location of the db is
C:\Program Files\3COM\VCX\VCX Call Reports\Db\vcxcdr.mdb
:)