2D arrays in 7.3... actually, parser bug?

zzzz=# select version();
version
------------------------------------------------------------------------
------------------------
PostgreSQL 7.3 on powerpc-apple-darwin6.3, compiled by GCC gcc (GCC)
3.1 20020420 (prerelease)
(1 row)

Being too lazy to RTFM, I decided to discover on my own if postgres
supported 2D array types:

zzzz=# create table foo (bar int8[][]);
CREATE TABLE

(Oh cool! it does!)

zzzz=# \d foo
Table "public.foo"
Column | Type | Modifiers
--------+----------+-----------
bar | bigint[] |

(hmm, that doesn't look right. <pause> *snicker* Hmm, I wonder...)

zzzz=# create table foo2 (bar int8[][][][][][][][]);
CREATE TABLE
zzzz=# \d foo2
Table "public.foo2"
Column | Type | Modifiers
--------+----------+-----------
bar | bigint[] |

So now my question is, since postgres doesn't support 2D (or N-D)
arrays, shouldn't the above produce some kind of syntax error?

eric