Hello
It is maybe not bug, but I didn't find any warning about this behavior.
select current_date + 1; -- ok
select 1 + current_date; -- not
ERROR: operator does not exist: integer + date
HINT: No operator matches the given name and argument type(s). You may
need to add explicit typecasts.
I use CVS version of PostgreSQL from last week
regards
Pavel Stehule