Bug in 7.2.1? -- ERROR: Adding columns with defaults is not implemented.

Using pg 7.1.2,  I can enter the following statement successfully:

# alter table manufacturer add column dummy integer not null default
1;

However, under 7.2.1, the same statement gets me --

ERROR:  Adding columns with defaults is not implemented.
        Add the column, then use ALTER TABLE SET DEFAULT.

My question is two-fold -- first, is this new behavior a feature, or a
bug?

Second, what features/fixes would i lose by reverting to 7.1.2?

I'd like to stick with 7.2.1, but this new behavior is making it
difficult for me.  I can't simply drop & recreate all my tables just
to add a column!

Any help would be appreciated!

adam