Java Update is not happening automatically on scheduled date / time

Tested OS : windows 2K / XP
Tested Build : mustang build 52

Steps to reproduce :

1. Install mustang build 52
2. Run Run1.reg and Run2.reg files (attached)
3. Schedule the date/time to daily at 4pm (the schedule can be Daily/weekly/monthly)
4. Change the time of test machine to 3:55pm
5. Logout and login to the test machine
When the system time reached 4:00pm, java update did not happen.

Expected Behaviour: Java Update should happen at 4:00pm
Actual Behaviour : Java Update is not happening at the scheduled date/time

Java Update setup is available at the following location :
/net/sqindia/export/disk10/j2se/test_results/java_update
Web URL :
http://sqindia.india.sun.com/disk10/j2se/test_results/java_update
xml files (mustang.xml and mustang_location.xml) location :
http://sqindia.india.sun.com/disk10/j2se/test_results/java_update/update

Note: Manual Update is working properly