Is this the only way to replicate data from Sun Directory Server Enterprise Edition to OpenDJ or OUD?
There is this free tool called LDAP Synchronization Connector.
Ldap Synchronization Connector synchronize data from any data source including databases, LDAPdirectories or files by reading, transforming and comparing these data between the source and the target referentials. These connectors can then be used to continuously synchronize a data source to a directory, for a one shot import or just to compare differences by outputting CSV or LDIF format reports.
In Azimuth Labs, we have used LSC on production sites when we migrated our customers' data from Sun Directory Server to ForgeRock OpenDJ. It works like a charm!