Class name is wrong or classpath is not set for : com.mysql.jdbc.jdbc2.optional.MysqlDataSource

http://stackoverflow.com/questions/17651423/unable-to-connect-to-jdbc-connection-pool-from-glassfish

https://code.google.com/p/groland3/downloads/detail?name=mysql-connector-java-5.0.5-bin.jar&can=2&q=

Hay que poner el driver aca
 mysql-connector-java-5.x.x-bin.jar copy to E:\Projects\glassfish3.1.1\glassfish\lib