That's not the behavior I see although it is the behavior in pre 1.3.x
Kerberos.

I set up my host to have 10-minute lifetime tickets and things
continue to work.  Here's klist output:

01/07/04 13:57:14  01/07/04 14:07:14  host/luminous.mit.edu@SUCHDAMAGE.ORG
01/07/04 14:15:16  01/07/04 23:58:01  imap/solipsist-nation.suchdamage.org@SUCHDAMAGE.ORG
01/07/04 14:22:29  01/07/04 14:32:29  host/luminous.mit.edu@SUCHDAMAGE.ORG