[Dovecot] exim and /var/run/dovecot/auth-client permissions

I am attempting to configure a dovecot 2.0 + exim + fetchmail (demon)
combination on openSUSE 11.4, initially with the standard dovecot package
(2.0.9-3.4-x86_64) and now with the later server:mail build service
package (2.0.11-1.1-x86_64).

I followed the instructions in
http://wiki2.dovecot.org/HowTo/EximAndDovecotSASL but despite the changes
in conf.d/10-master.conf the permissions on /var/run/dovecot/auth-client
remain unchanged:

$ ls -l /var/run/dovecot/auth-client Srw------- 1 root root 0 Mar 14 13:11 /var/run/dovecot/auth-client $

This is probably the cause of authentication failures from exim. I
suspect it is something trivial but haven't yet been able to find the
answer.