oh dear ...

This worked in 7.3:

regression=# select '1999-jan-08'::date;
ERROR:  date/time field value out of range: "1999-jan-08"
HINT:  Perhaps you need a different "datestyle" setting.

Setting DateStyle to YMD doesn't help, and in any case I'd think that
this ought to be considered an unambiguous input format.

The variantsselect 'jan-08-1999'::date;select '08-jan-1999'::date;
both still work, so I think this is probably some small oversight in the
logic, but I haven't dug into it to find where.

Not sure if this qualifies as a must-fix-for-7.4 or not, but my vote
would be "yes" ...
        regards, tom lane