Claude,
I think tacacs administration in ACS SE 4.2 is same as device commands report in ACS express 5.0
Device Commands Report
The Device Commands Report option enables you to generate device command reports that include information about device commands used by all users and all devices. The default device commands report you generate will list device commands used by all users and all devices for the current day.
To generate a report for a specific day, user, or device, check the Specific check box, then select the date or enter the user or device name in the field provided.
Click Generate Report to initiate the report. A dialog box asks if you want to open the report or save the file to disk. The default report reader format is Microsoft Office Excel.
Device Commands Report
http://www.cisco.com/en/US/docs/net_mgmt/cisco_secure_access_control_server_express/5.0/user/guide/reports.html#wp1042924
Regds,
JK
Do rate helpful posts-
~Jatin