windows 2000 domain controllers and sync-ing time with external time source

I have three domain controllers - dc01, dc02 & dc03. dc01 has the pdc
emulator service. These domain controllers were not initially sync-ed
with an external time source. Please let me know how I can sync this
with an external time source.

I tried the below, but it will not work out totally:
changed the server type on dc01 to NTP:
a. Locate and then click the following registry subkey:
HKEY LOCAL MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters

b. In the right pane, right-click TYPE, and then click Modify.
c. In Edit Value, type NTP in the Value data box, and then click OK.

Set the external time source using the below command
net time /setsntp:time.windows.com

Stopped the time service and started it. The new time took effect on
dc01.

The other domain controllers dc02/dc03 have the registry value of
"type" under HKEY LOCAL
MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters as
"nt5d5".

DC02 & DC03 never got the time sync-ed with dc01 automatically. So, it
sync-ed up dc03 with dc01 using net time /setsntp:dc01. dc03 got the
new time from dc01 after this, but the new time changed automaticall
later on with the below event

Time service corrected the clock error by 392 seconds

Please let me know how you think I can get this fixed.