Are you having trouble running it in the Designer, or on the server. You need to update the classpath for both cases.
For instructions on how to tweak the classpath in the Designer, download our SQLPlus qpac which includes a document that explains one way of doing this.
On the server, the easiest way is just to drop the jar file into the lib directory, and then restart the server.
Howard
http://www.avoka.com