Parser bug?

I think this is a bug in 6.4:

bray=> select rcname, rcsrc from pg_relcheck where rcrelid = '115404'::oid and 
rcrelid in (select min(rcrelid) from pg_relcheck group by rcname);
ERROR:  parser: Subselect has too many or too few fields.

The subselect only produces one column; so I think that the error message 
is wrong.

-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver              PGP key from public servers; key
ID32B8FAA1                ========================================    "The LORD is nigh unto all them that call upon
him,to     all that call upon him in truth."                                          Psalms 145:18