Cause of problem: Click audit trail button results in sql query with a base_name criteria that does not take into account the configured dbprefix. Hence, when the system is configured without dbprefix this will not generate any problems, but when a dbprefix is configured the audit trail button won't return any records as the base_name does not match with what is stored in the audit database audit_tbl.
Solution: Change line 251 and line 255 in file include.session.inc from
$database_id = $dbobject->dbname;
to
$database_id = $dbobject->dbname_server;