olcMirrorMode FALSE - yet - error code 53 - shadow context; no update referral

[lejeczek]

hi everybody

one of databases in my slapd has nor referrals and 
olcMirrorMode=FALSE in config
yet I get infamous:
- [LDAP: error code 53 - shadow context; no update referral]

why would it be, something I am missing in the config of 
that database?
other databases configs affect this one somehow?

many thanks