There are a lot of totally different ways to do this, and which one results
in the least lines of perl probably depends on how your script works. The
methods that I find most interesting are:

1. Create the list with this confirmation disabled (via a simple change in
your creation template). Have the script flip the option the next day.
Realistically, the address won't manage to get any significant spam during
the first day of its life (probably no spam at all).

2. Overwrite a template for an obscure function that a normal owner will not
even know about, let alone in the first minutes of the life of his new list.
Send a job with three commands: one to store the template, one to trigger
the template, and one to reset it.

3. Send the command from a special, one-time sendmail alias that you create
together with the other aliases. This pipes into a script that sends an OK
reply. Delete that special mailbox the next day.

  Eric