NTDS Replication Error between DCs: Event ID: 1645 and 1586

Domain with two Windows 2003 DCs had issues with NRDS replication with bellow errors. Tme was more than 10 minute different on one of the DCs, changing the time solved this issue.

Event Type:    Error
Event Source:    NTDS Replication
Event Category:    DS RPC Client
Event ID:    1645
Date:        05/09/2011
Time:        11:39:23
User:        NT AUTHORITY\ANONYMOUS LOGON
Computer:    DC1
Description:
Active Directory did not perform an authenticated remote procedure call (RPC) to another domain controller because the desired service principal name (SPN) for the destination domain controller is not registered on the Key Distribution Center (KDC) domain controller that resolves the SPN.
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Event Type:    Warning
Event Source:    NTDS Replication
Event Category:    Replication
Event ID:    1586
Date:        9/5/2011
Time:        2:24:01 PM
User:        NT AUTHORITY\ANONYMOUS LOGON
Computer:    DC2
Description:
The Windows NT 4.0 or earlier replication checkpoint with the PDC emulator master was unsuccessful.
 
A full synchronization of the security accounts manager (SAM) database to domain controllers running Windows NT 4.0 and earlier might take place if the PDC emulator master role is transferred to the local domain controller before the next successful checkpoint.
 
The checkpoint process will be tried again in four hours.