I've googled for you a bit, and the drivers being used seems to be everyone's favourite answer.
http://www.orafaq.com/msgboard/java/messages/862.htm Just for the heck of it, try to comment out the DriverManager.registerDriver() line. This is usually not needed, and may in fact be the line that causes this error.
[ July 16, 2002: Message edited by: Mike Curwen ]