refcursor and number of records

Hi all,

After running a rather large query (30+ seconds) a resultset will be
returned. That resultset can be anywhere from 1 to 1500 records. To
reduce frontend memory requirements, I would like to create a function
that returns a refcursor for the query and just fetch 10 records at a
time from the frontend. But I would also like to show "displaying
records 11 to 20 of 1443". I just can't figure out how to get the number
of records in the cursor without fetching them all. Any suggestions on
how to get this number (1443 in the example)?

JDBC
PostgreSQL 7.2.1

Jochem