slurpd replication and openldap versions

hi

i want to know in general what the caveats are when replicating ldap data with slurpd between openldap servers of different major versions. i would be especially interested in knowing if it is adviseable to replicate from a 2.3 master to 2.2 slaves (or the other way round). the reason for asking this is that i have noticed that in the present setup replication from 2.0 to 2.2 produces .rej files which are 10 times bigger than those resulting from "same generation" (2.0 <-> 2.0) replication. or are there any special configuration options for this situation?

thanks for help matthias