As of Cisco Unified Communications Manager (CUCM) 8.5.1 and later there is an overview log file, calllogs*.txt. This file can be downloaded using the Real Time Monitoring Tool (RTMT) or viewed from the command line command "file view activelog /cm/trace/ccm/calllogs/calllogs_*.txt.gz".
The file looks like this when viewed.
2012/06/19 09:56:29.370|CC|SETUP|28086337|28086338|2000|918005532447|918005532447
2012/06/19 09:56:29.372|SIPT|28086308|UDP|OUT|192.168.1.2|5060|SIPTrunk|192.168.1.1|5060|1,100,50,1.123550166^192.168.1.178^SEPABCDACBDACBD|5532447|90396a00-fe01850d-3ae39-2e1090a@192.168.1.2|INVITE
The file is "|" delimited and can be decoded by looking at the corresponding field number below.
Format for Message Type - Call Control (CC in the 2nd field)
1) Timestamp (2012/06/19 09:56:29.370)
2) Message type (CC)
3) Operation (SETUP)
4) Call Identifier for call leg 1 (28086337)
5) Call identifier for call leg 2 (28086338)
6) Calling number (2000)
7) Original called number (918005532447)
8) Final called number (918005532447)
Format for Message Type - SIP (SIPT in the 2nd field)
1) Timestamp (2012/06/19 09:56:29.372)
2) Message type (SIPT)
3) My call idenfier (28086308)
4) Protocol (UDP)
5) Direction (OUT)
6) Local IP (192.168.1.2)
7) Local port (5060)
8) Device name (SIPTrunk)
9) Device IP (192.168.1.1)
10) Device port (5060)
11) Correlation ID (1,100,50,1.123550166^192.168.1.178^SEPABCDACBDACBD)
12) Message Tag (5532447)
13) SIP call-id (90396a00-fe01850d-3ae39-2e1090a@192.168.1.2)
14) SIP Method (INVITE)
