MSExchangeAL/MSExchangDSAccess Errors in Application Log (2103, 8026, 8250)

I'm getting the following three events in my Application log.  I'm not sure if they're directly related, but they seem to happen at the same time.  The OS was installed about 2 months ago, but these errors just started happening within the last 2 weeks.

Event Type:      Error
Event Source:      MSExchangeAL
Event Category:      Service Control
Event ID:      8250
Date:            7/16/2006
Time:            3:00:37 AM
User:            N/A
Computer:      [Server Name]
Description:
The Win32 API call 'DsGetDCNameW' returned error code [0x862] The specified component could not be found in the configuration information.  The service could not be initialized.  Make sure that the operating system was installed properly.


Event Type:      Error
Event Source:      MSExchangeAL
Event Category:      LDAP Operations
Event ID:      8026
Date:            7/16/2006
Time:            3:00:37 AM
User:            N/A
Computer:      [Server Name]
Description:
LDAP Bind was unsuccessful on directory theserver.millsentertainment.office for distinguished name ''. Directory returned error:[0x51] Server Down.


Event Type:      Error
Event Source:      MSExchangeDSAccess
Event Category:      Topology
Event ID:      2103
Date:            7/16/2006
Time:            3:00:34 AM
User:            N/A
Computer:      THESERVER
Description:
Process MAD.EXE (PID=2876). All Global Catalog Servers in use are not responding:
[server name].[domain].office