Pesistance Unit with netbeans

Hi ,
i am a newbie to netbeans ... when i tried to make a Persistent project using the option Create entity objects from existing relational database , no table list from db is populated. My db connectivity and jdbc driver configurations are correct .... i have to do any further configuration to create the entity objects from the database ? or is this an issue from netbeans side ? have anybody faced such a problem before and know the resolution for the same ?

Thanks in advance
Regards sajith