Please try this patch ftp://ftp.openldap.org/incoming/pierangelo-masarati-2010-04-29-chain.1.patch, posted some time ago in partial response to ITS#6540 and report. Thanks, p.
I will give the patch a try.
What is the patch doing? I am guessing it will fix the illegal configuration problem.
It comments some braindead checks that I don't even remember what were there for, that prevent reloading a valid configuration from cn=config. Consider that back-config support in back-ldap was added during the development of back-config itself, so some odd configuration cases that worked at that time might no longer be valid now.
Should I use the configuration I gave above or should it be modified?
The configuration should be fine; even the contents of the configuration database (back-config) should be valid. After applying the patch, slapd should restart fine, loading slapo-chain(5) as it is configured now.
p.