Schema change in master-slave setup

[Andre Nathan <andre@digirati.com.br>]

Hello

I have an openldap master-slave setup, and I need to make a simple
schema change to add an attribute to an objectclass which is defined as
below:

objectclass ( dgMail:1.2.2 NAME 'dgMailAuth'
    DESC 'SASL Authentication for mail'
    SUP top
    STRUCTURAL
    MUST dgDBID
    MAY ( uid $ userPassword $ mail ) )

I just need to add an attribute called mailDrop, which is already
defined in the schema, but only used in other objectclasses, so the last
line would become

    MAY ( uid $ userPassword $ mail $ mailDrop ) )

My question is: is it safe to do this one server at a time, editing the
schema file and restarting the daemon, or will I have problems with the
temporary schema mismatch? I would like to minimize the downtime of the
operation, since the system is heavily used in production.

Thanks in advance,
Andre