date_part function

I was putzing around with the date/time functions to get a feel for how
they work, when I ran across this bit of puzzling behavior.  I'm running
PostgreSQL 7.0.3 on a Red Hat 6.1 box.

I submitted the following query:

     select date_part('dow', timestamp 'now');

and received the following results:

     ERROR:  Function 'date_part(text, timestamp)' does not exist
      Unable to identify a function which satisfies the given
     argument types
      You will have to retype your query using explicit typecasts

However, the user documentation seems to indicate that this function is
an integral part of PostgreSQL.

What gives?

Regards,

--
John Burski
Chief IT Cook and Bottlewasher
911 Emergency Products, St. Cloud, MN
(320) 656 0076

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