Log from ispconfig:
03.02.2013-15:35 - DEBUG - Set Lock: /usr/local/ispconfig/server/temp/.ispconfig_lock
03.02.2013-15:35 - DEBUG - No Updated records found, starting only the core.
03.02.2013-15:35 - DEBUG - Remove Lock: /usr/local/ispconfig/server/temp/.ispconfig_lock
Thats ok. Maybe you deleed records from sys_datalog table or emptied that table. In this case the system is not able to find changes as the new change records start at ID 1 again.
the solution in this case would have been to set the value of the updated clumn in the server table to the last processed value from sys_datalog.