Error: 18452, Severity: 14, State: 1.

This error is showing up in the application log errors for all MSSQL Database monitors we have configured. Here is the full error and it occurs every time the monitor polls. 2008-03-05 17:16:09.83 Logon Error: 18452, Severity: 14, State: 1.
2008-03-05 17:16:09.83 Logon Login failed for user ''. The user is not associated with a trusted SQL Server connection. [CLIENT: 172.25.246.53]

From the applications manager side everything looks fine but our DBAs want/need this fixed.
Here are some links I found while trying to troubleshoot this issue myself:
http://support.microsoft.com/kb/265808
http://blogs.msdn.com/sql_protocols/archive/2005/09/28/474698.aspx
http://msdn2.microsoft.com/en-us/library/ms366351.aspx

Thanks,
Chris
Chris Patterson