Issues with connection Pool (1 reply)

i have an issue trying to connect through connection pooling with mysql5.0 and connector j 5.0 in tomcat and glassfish, was trying to make it work but it returns that
cannot cast javax.sql.DataSource into Driver for a url=null

i followed the steps of the tomcat tutorial and also trying to configure the conn pool in glassfish and same issue, does anybody have any idea?

thanks.-