Howard,
Our security expert at Sun consider that the attack could be applied to
LDAP, although it will be more complex to achieve for all the good
reasons you've outline (session-oriented, with explicit authentication
attached to a session, and is a record-oriented ASN.1 encoded protocol
with precisely defined message structure).
The renegotiation in the attack is as far as I understand, driven by the
man in the middle, and so even though OpenLDAP slapd never request the
renegociation, it is still subject to the attack.