Posting a learning.
We tried using the old version Lotus Domino Toolkit for JAVA/CORBA Release 2.1 and it did not work with a Domino server Release 6.5 and EP 6.0 SPS12. Version 2.1 of the toolkit was the only version we could find for download from the IBM web site.
Symptom was: Index server Application Log was reporting Error: XCrawlerService Retriever thread domino_test_rbl_LotusNotes failed - java.lang.NoClassDefFoundError
Prakash V. sent us the Lotus Domino Toolkit for JAVA/CORBA Release 5.0.8 and it worked fine for this scenario. Thanks Prakash!
RBL