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 functions
Result data type | Schema | Name | Argument data types
------------------+------------+----------+------------------------
interval | pg_catalog | interval | reltime
interval | pg_catalog | interval | text
interval | 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
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