For information to those that may interested (and for the record)...

Here is a simple description of the openldap <-> Outlook ldap addressbook issue:
Source: http://victor-sudakov.livejournal.com/124269.html
Translation: http://translate.google.co.uk/translate?hl=en&sl=ru&u=http://victor-sudakov.livejournal.com/124269.html&prev=search

In addition, for the address list organization to be displayed in Outlook, it seems necessary to patch the file /etc/openldap/schema/core.schema in order to add 'company' attribute as alias to 'o', something like:

attributetype ( 2.5.4.10 NAME ( 'company' 'o' 'organizationName' ) DESC 'RFC2256: organization this object belongs to' SUP name )

Source: http://habrahabr.ru/post/183996/
Translation: http://translate.google.co.uk/translate?hl=en&sl=ru&u=http://habrahabr.ru/post/183996/&prev=search

Not sure to which version of Outlook this would apply...

Also it seems possible to modify the LDAP core schema attributes without recompiling...
 
Please note that the following:
- has not been tested and may not be fully accurate
- is not recommended as you loose RFC compliance

- does not apply directly to CN attribute as required for Outlook addressbook (http://www.openldap.org/cgi-bin/wilma_hiliter/openldap-technical/201001/msg00077.html) but process would be very similar...

- may require an openldap version that allow core schema modification (2.4 or upper)

===
Method1 (update core schema attribute via ldapmodify)

    Something like...
    Source: https://lists.forgerock.org/pipermail/opendj/2013-May/002995.html

    "...

  ldapmodify -D cn=root -w password -p 1389
  dn: cn=schema
  changetype: modify
  delete: attributetypes
  attributetypes: ( 2.5.4.42 NAME 'givenName' SUP name X-ORIGIN 'RFC 4519' )
  -
  add: attributetypes
  attributetypes: ( 2.5.4.42 NAME 'givenName' SUP name ORDERING caseIgnoreOrderingMatch X-ORIGIN 'RFC 4519' )

    ..."

    Of course that would need to be adapted to the openldap process and schema definition, as per version in use...

===
Method2 (edit core schema file core.ldif) - Obviously it is not recommended to directly edit core schema ldif files.
Source: https://freeswitch.org/confluence/display/FREESWITCH/Polycom+Corporate+Directory

  "...
  Add caseIgnoreOrderingMatch to core.schema

  We now have to add "ORDERING caseIgnoreOrderingMatch" to the surname- and givenName-Attributes, because Polycom uses simple search expressions like '>=' and '<=' when querying the LDAP-addressbook.

  root# /etc/init.d/slapd stop
  root# vim /etc/ldap/sapd.d/cn\=config/cn\=schema/cn\=\{0\}core.ldif
  In this file,

    substitute surname original
    olcAttributeTypes: {1}( 2.5.4.4 NAME ( 'sn' 'surname' ) DESC 'RFC2256: last (family) name(s) for which the entity is known by' SUP name )

    with surname ORDERING
    olcAttributeTypes: {1}( 2.5.4.4 NAME ( 'sn' 'surname' ) DESC 'RFC2256: last (family) name(s) by which the entity is known' SUP name ORDERING caseIgnoreOrderingMatch)

   Replace givenName original
   olcAttributeTypes: {35}( 2.5.4.42 NAME ( 'givenName' 'gn' ) DESC 'RFC2256: first name(s) for which the entity is known by' SUP name )

   with givenName ORDERING
   olcAttributeTypes: {35}( 2.5.4.42 NAME ( 'givenName' 'gn' ) DESC 'RFC2256: first name(s) by which the entity is known' SUP name ORDERING caseIgnoreOrderingMatch)

  start slapd
  root# /etc/init.d/slapd start
  ..."

Just thought that may be helpful to know and record on the forum...