I’ve seen the following situation. Ibot running perfectly fine on the development server, however, it started to fail the production with the above-mentioned error 68019. The security nature of it made me look into the instanceconfig.xml and cryptotools – since I’ve figured that this was the case. It seems as I was right as something got corrupted on the security side. After re-running cryptotools – everything went back to normal. Also, you can view these Oracle links in this in case you meet this problem:
http://forums.oracle.com/forums/thread.jspa?threadID=499157&tstart=0