This is what I have on Plesk 8.0.1
*/15 * * * * /usr/local/psa/admin/sbin/backupmng >/dev/null 2>&1
0 1 * * 1 /usr/local/psa/libexec/modules/watchdog/cp/secur-check
0 1 * * 1 /usr/local/psa/libexec/modules/watchdog/cp/send-report weekly
0 3 * * 7 /usr/local/psa/libexec/modules/watchdog/cp/clean-reports
10 1 * * * /usr/local/psa/libexec/modules/watchdog/cp/clean-sysstats
14 5 * * * /usr/local/psa/bin/mysqldump.sh >/dev/null 2>&1
15 1 * * * /usr/local/psa/libexec/modules/watchdog/cp/pack-sysstats day
15 1 * * 1 /usr/local/psa/libexec/modules/watchdog/cp/pack-sysstats week
15 1 1 * * /usr/local/psa/libexec/modules/watchdog/cp/pack-sysstats month
15 1 1 * * /usr/local/psa/libexec/modules/watchdog/cp/pack-sysstats year
17 7 * * * /usr/local/psa/admin/bin/php /usr/local/psa/admin/plib/report/autoreport.php --auto daily >/dev/null 2>&1
17 7 * * 1 /usr/local/psa/admin/bin/php /usr/local/psa/admin/plib/report/autoreport.php --auto weekly >/dev/null 2>&1
17 7 1 * * /usr/local/psa/admin/bin/php /usr/local/psa/admin/plib/report/autoreport.php --auto monthly >/dev/null 2>&1
20 1 * * * /usr/local/psa/libexec/modules/watchdog/cp/clean-events
7 4 * * * /usr/local/psa/admin/sbin/statistics >/dev/null 2>&1