Driver for Postgres 7.2

Hi
I want to communicate my Java application(JDK 1.4.2) with one database
Postgres 7.2.
I have downloaded driver jdbc (pg72jdbc2) but I found one error in my
application: org.postgresql.Driver not found.

I don´t know if I am using correct version of this driver or I need other
driver, in this case somebody could me where I can download this driver?

Thanks in advance
David