Migrating from previous version of Sun Java System Directory Server to the latest 7.0 release is simple.
The Directory Server migrating can be broken down into the following distinct steps:
1. Migrating the Schema
2. Migrating the Security Settings
3. Migrating the Configuration
4. Migrating the Data
5. Migrating the Plug-Ins
6. Post-migration tasks
Migration can be done automatically or manually. I prefer the manual approach where I have more control.