(really stupid) Zone file question

[Fred]

While we are on the subject of zone files, I have a small dilemma which
I simply don't have the time to work out:

I have a name server running on computer A. I've just acquired computer
B, and I want that to be a slave NS to computer A.

There is a *per zone* way of doing this with Bind. Problem is, I am
adding domain names -- zones -- frequently to computer A, and want a way
to slave *everything* automatically to computer B. On cursory look into
the Bind docs, I see no obvious way to set this up.

So, I'm thinking of simply setting up a cron job to rsync the zone files
from A to B, but there are some obvious problems with this approach, the
least of it is that it's kludgey. 

Is there a *proper* way to make sure B gets all the new zone additions
from A -- and deletions as well? Or should I employ the kludgey rsync
approach with probably the addition of a script to remove deleted zones?

I keep thinking there must be a really dirt-simple answer to this. Alas,
I've got 50 things hanging over my head right now...

-Fred