ACL filter and backend SQL

[Jaime Tomé Gomes Ventura <jaimeventura@ipp.pt>]

I'm using openldap 2.2.23 and backend sql as module.
I cant get this rule to work:

Basically, allow bind only to users having attribute ippNetStatus = ACTIVO.
access to * filter=(ippNetStatus=ACTIVO)
      by anonymous auth
      by self write

I've made a replication to a bdb database and this rule works just fine 
on it .

Is this a backend-sql bug?

Thanks
   Jaime