epoch

Trying example from:

http://www.postgresql.org/devel-corner/docs/user/functions-datetime.html

patrimoine=# SELECT EXTRACT(EPOCH FROM TIMESTAMP '2001-02-16 20:38:40');
ERROR: parser: parse error at or near "epoch"
patrimoine=# select version();
version
-------------------------------------------------------------------------------
PostgreSQL 7.1beta3 on i386-unknown-netbsdelf1.5Q, compiled by GCC egcs-1.1.2
(1 row)

patrimoine=# select date_part('epoch','2001-02-16 20:38:40'::timestamp);
date_part
-----------
982355920
(1 row)

Is my version already too old?

Cheers,

Patrick