Credentials Cache File Problem Running with 'cron'

[Dennis Putnam]

I have what I thought was a perl problem using Kerberos  
authentication. However, after many emails with perl experts, the  
consensus is that this is really a problem with the Kerberos library.  
Hopefully, someone on this list will recognize the problem an can  
suggest a solution.

This particular script runs fine when executed from the command line  
(I'm using OS X 10.4.11). When the same command is run from 'cron' or  
'at' the following error occurs:

Credentials cache I/O operation failed XXX

I am told that this error indicates there was a problem writing the  
credentials cache file. The first thought was that it had to do with  
permissions but the script does the same thing even running as root.  
The second thought was that it had to do with an environment variable  
but again that is not the case since perl runs in its own environment  
so the variables are identical running from command line or 'cron'. At  
that point, the author of the perl interface said that all his code  
does is make standard Kerberos library calls. Since Apple uses the  
standard MIT libraries, the conclusion is that this must be something  
specific to the library rather then perl or the OS. Can anyone help?  
TIA.