There are two issues with Schema 1 in Communications Express:
If you are running Communications Express with Sun LDAP Schema 1, before running the Communications Express configuration program, you must add the DC root node to your LDAP using ldapmodify. The entry should look like this:
dn: o=internet objectClass: organization o: internet description: Root level node in the Domain Component (DC) tree
The calendar utility used to provision users in Schema 1, csuser, was designed for Calendar Express and does not enable a user for Address Book service as is needed for Communications Express.