Seems the jdbc driver is not loaded for pooled connection, hence it is giving an error while intializing the apache connection  pool. Make sure you have all the required jar files (including the ones supplied with MySQL database containing the jdbc drivers) in the “/WEB-INF/lib” directory of your application  if it is an application level pool or in the web  server’s “lib” directory if you are creating server level connection pool (which seems you current option). I hope replacing missing jar files will resolve the issue.