I couldn't locate any information on Apple or elsewhere on what the proper format for the LDIF file Address Book was expecting, so I thought I would post what worked for me:
dn: cn=David Martin,mail=davidfmartin@yahoo.com objectClass: top objectClass: person objectClass: organizationalPerson objectClass: inetOrgPerson givenName: David sn: Martin cn: David Martin mail: davidfmartin@yahoo.com TelephoneNumber: 303-555-1212 FacsimileTelephoneNumber: 303-555-1313 Pager: 303-555-1414 Mobile: 303-555-1515 homePostalAddress: 17/275-09 ou: 3100 O: You company name here description: Mailstop - 12275, any addl. comments.Once I knew the format, it was then a simple task to create a template I could use in a Perl program that would convert a proprietary contact database to LDIF, and then import that into Address Book.
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