Need Postgresql Help

Respected sir,
             Atul Pedgaonkar here from India. I am using postgresql7.2 as backend and for front-end, perl5.6.1. I need some help regarding postgresql-stored procedure. The problem is like this

        1)How to create stored procedure in postgresql?
        2)How can i use it from perl script with parameters. ?
        3)How to return resultset from that Stored Procedure ?

I hope your kind co-operation.
Thank You,

Regards,

Atul…