Postgresql with Play Framework

Im trying to use Postgresql with Play for their Yabe tutorial and get this error:

Cannot connected to the database, Driver not found (org.postgresql.Driver)

Here is my connection string:

# If you need a full JDBC configuration use the following :
 db.url=jdbc:postgresql:yabe
 db.driver=org.postgresql.Driver  
 db.user=yabe
 db.pass=yabe
#
# Connections pool configuration :
 db.pool.timeout=1000
 db.pool.maxSize=30
 db.pool.minSize=1

In my lib folder I have this: postgresql-9.1-901.jdbc3.jar

I tried changing the driver name to the same name is tha jar but still get the same error. Any ideas?