Are you sure you are following what is said here? (have you updated web.xml, have you tried using context instead of resource)?
Also, is your database running locally. If yes, can you try using localhost instead of IP?
Are the port numbers, database name, userid, password correct and has got enough privileges? (remember case-sensitivity)
Do post back, if you are still getting this issue.
If you are not laughing at yourself, then you just didn't get the joke.