unknown error occuring while using mit kerberos implementation

[Steve]

Hi I have a working (gssapi) kerberos authentication mechanism built
into an application which is currently being deployed.  It has been
bullet proof for the last month then recently at one location I am
receiving errors.  It was working at the location for almost one month
then out of no where it stopped working.  Here is a sample from gssapi
logs from the server.:

2009-12-09 10:42:14,307 DEBUG root - [GSSKerberos:getGSSInternalName]
Entering function
2009-12-09 10:42:14,338 INFO  root -
[GSSKerberos:acceptSecurityContext]GSS_ACQUIRE_CRED being called
2009-12-09 10:42:14,354 INFO  root -
[GSSKerberos:acceptSecurityContext]GSS_ACCEPT_SEC_CONTEXT being called
2009-12-09 10:42:14,354 ERROR root -
[GSSKerberos:acceptSecurityContext]Error in gss_accept_sec_context
(GSS_S_DEFECTIVE_TOKEN)
2009-12-09 10:42:14,354 DEBUG root - [GSSKerberos:get_status_message]
Entering get_status_message
2009-12-09 10:42:14,354 ERROR root - [GSSKerberos:get_status_message]
GSS-API error: Invalid token was supplied

2009-12-09 10:42:14,354 DEBUG root - [GSSKerberos:get_status_message]
Entering get_status_message
2009-12-09 10:42:14,354 ERROR root - [GSSKerberos:get_status_message]
GSS-API error: No error

2009-12-09 10:42:14,354 ERROR root -
[NetworkSecurity:AcceptClientToken]GSS Security context failed.

So it looks like an invalid token was passed from the client.
Something must have changed in the server environment but I am having
a hard time tracking it down.  I was hoping some one could provide
some clues to where I can research.  I reviewed the environment and it
looks like all the krb5.ini & environment variables are the same.

Thanks for the help in advance.

Steve