kscreensaver and kerberos, strange behaviour

[Erwan David <erwan@rail.eu.org>]

	Hi,

I have kerberos authentication on my debian (through
lib_pamkrb5). Upon login (through kdm), my tickets are in
/tmp/krb5cc_<uid>_<random> and KRB5CCNAME is setup accordingly (that's
the documented behaviour of libpam-krb5).

However, sometimes (but not always), when I unlock my kde session
(locked by kscreensaver), this file disappeared, and I instead have a
credential cache under /tmp/krb5cc_pam_<random>

So all my apps relying on kerberos do not work since they check the
wrong file for ticket. There clearly is a bug somewhere, but where ?
In libpam-kb5, or in kscreensaver, or some helper ? (eg
kscreenlocker_greet or kcheckpass (I straced the kscreenlocker_greet
process and saw it calls kcheckpass, which in turn uses lib_pam with
the kdm service name).

What should I do about this ?