Hrm. interval() function?

While doing the previous post, I found that the following fails, should it?

PG 7.3.2 on FreeBSD:


ler=# \df interval                        List of functionsResult data type |   Schema   |   Name   |  Argument data
types
------------------+------------+----------+------------------------interval         | pg_catalog | interval |
reltimeinterval        | pg_catalog | interval | textinterval         | pg_catalog | interval | time without time zone
 
(3 rows)

ler=# select interval('6 months');
ERROR:  parser: parse error at or near "'6 months'" at character 17
ler=# select interval('6 months'::text);
ERROR:  parser: parse error at or near "'6 months'" at character 17
ler=#
-- 
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 972-414-9812                 E-Mail: ler@lerctr.org
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