lookups on multivalued field fails

[kevin@hcico.com]

I am experiencing a very strange problem.  I am trying to do lookups from
my mail system directly into the LDAP server.  After several unsuccessful
attempts, I decided to try the querries in other ways.  The bottom line is
that I do not seem to have my OpenLDAP set up correctly.  I am
experiencing not only lookup failures in Postfix, but also SaslAuthd and
the command line.  So, my first order is to look at the command line, and
see if I can figure out what is wrong there.  However this seems to be
quite puzzling.  I can look up a record by the mail field, but not the
mailAlternateAddress fields:

[root@ruby root]# ldapsearch -x uid=kevin mail mailAlternateAddress
# extended LDIF
#
# LDAPv3
# base <> with scope sub
# filter: uid=kevin
# requesting: mail mailAlternateAddress
#

# Kevin Fries, People, example.com
dn: cn=Kevin Fries,ou=People,dc=example,dc=com
mail: Kevin.Fries@example.com
mailAlternateAddress: kfries@example.com
mailAlternateAddress: kgf@example.com
mailAlternateAddress: kevin@example.com

# search result
search: 2
result: 0 Success

# numResponses: 2
# numEntries: 1

[root@ruby root]# ldapsearch -x mail=kevin.fries@example.com mail
mailAlternateAddress
# extended LDIF
#
# LDAPv3
# base <> with scope sub
# filter: mail=kevin.fries@example.com
# requesting: mail mailAlternateAddress
#

# Kevin Fries, People, example.com
dn: cn=Kevin Fries,ou=People,dc=example,dc=com
mail: Kevin.Fries@example.com
mailAlternateAddress: kfries@example.com
mailAlternateAddress: kgf@example.com
mailAlternateAddress: kevin@example.com

[root@ruby root]# ldapsearch -x mailAlternateAddress=kevin@example.com
mail mailAlternateAddress
# extended LDIF
#
# LDAPv3
# base <> with scope sub
# filter: mailAlternateAddress=kevin@example.com
# requesting: mail mailAlternateAddress
#

# search result
search: 2
result: 0 Success

# numResponses: 1

In slapd.conf I have both of these lines, so that searches are optomized:

index   mailAlternateAddress     eq
index   mail                     sub,eq

So why can I find a person by primary email address, but not an alias
address?  This seems strange to say the least.

I also thought that it could be the schema (i.e. can't search by fields
defined in the qmailuser schema), but I am able to search by
mailMessageStore and retrieve the correct record.  So, that theory got
blown to heck in a hurry.  So I am back to the multivalued field as the
most likely culprit.

TIA for any and all help.

Kevin Fries