Since you had some success with camel-ldap, I would suggest you look at how the the camel-ldap component binds to the ldap server and do something similar.
You are correct, the camel-ldap component does not currently support adding objects to the ldap server, but another thing you could try is add that support yourself and hopefully submit a patch, or open a jira at apache. Usually, when there is enough interest in a particular improvement a committer will take up the task. Contributions are highly appreciated.
I work with an LDAP repository and would suggest you check out the Spring LDAP project. This project is designed to simplify LDAP access and can be used to build services for LDAP connectivity.
The ServiceMix/ESB platform is about integrating applications - not repositories. Services should be designed to interact with repositories in the manner your business logic requires. ServiceMix can then be used to integrate those services as required.