_sasl_plugin_load failed on sasl_canonuser_init for plugin: ldapdb

[Marten Lehmann]

Hello,

I configured cyrus to use saslauthd for authentication. The related 
lines in /etc/imapd.conf are as follows:

sasl_mech_list: PLAIN
allowapop: no
sasl_pwcheck_method: saslauthd
sasl_auto_transition: no

Now, everything works fine, SASL-Authentication, LMTP, POP3, IMAP, with 
just one problem: /var/log/auth.log is filling up with lines like this:

cyrus/lmtp[6233]: canonuserfunc error -7
cyrus/lmtp[6233]: _sasl_plugin_load failed on sasl_canonuser_init for 
plugin: ldapdb
cyrus/lmtp[6233]: auxpropfunc error invalid parameter supplied
cyrus/lmtp[6233]: _sasl_plugin_load failed on sasl_auxprop_plug_init for 
plugin: ldapdb
cyrus/lmtp[6233]: canonuserfunc error -7
cyrus/lmtp[6233]: _sasl_plugin_load failed on sasl_canonuser_init for 
plugin: ldapdb

But I nowhere configured cyrus to use auxprop authentication or the 
ldapdb plugin. Also, openldap is running on a different server so all 
that cyrus should use is saslauthd which indeed works. But I cannot live 
with that mass of errors in the logfile, even though they don't seem to 
harm anything.

What is causing them?

Kind regards
Marten