Kerberos error from Vista workstations

I am getting the following error from selected Vista workstaions on my
domain. I know we have other Vista machines on the network that aren't
throwing this error.

Severity: Error
Status: New
Source: KDC
Name: Miscellaneous KDC Errors
Description: While processing an AS request for target service krbtgt, the
account <username> did not have a suitable key for generating a Kerberos
ticket (the missing key has an ID of 2). The requested etypes were 18. The
accounts available etypes were 23 -133 -128 3 1.
Domain: <domain name>
Agent: <domain controller name>
Time: 7/21/2006 13:15:50

This output is from MOM on our domain controller.

Thanks,

Dan