StartTLS API activation not Working with addExtendedOperationHandler()

To activate StartTLS - the following code should work :

ldapServer.setEnableLdaps(false)
ldapServer.addExtendedOperationHandler(new
StartTlsHandler());
ldapServer.start();

However it does not because addExtendedOperationHandler is not correctly implemented.

This code does work to startTLS

Collection<ExtendedOperationHandler> handlers =
new ArrayList<ExtendedOperationHandler>();
handlers.add(new StartTlsHandler());
ldapServer.setExtendedOperationHandlers(handlers);