Mailman allow open subscribe

[npowless]

I am considering bringing a client over to hostgator from their current host, which runs DirectAdmin (and therefore majordomo as the mailing list package).

I have a custom built member management software that they use to add/remove members, etc. This software integrates with majordomo to update the mailing list subscription preferences for the members.

If I bring them over, I will have to migrate them to mailman instead of majordomo, but my major concern is how the software adds email addresses. It appears that mailman won't let me select an open subscribe policy (aka don't send confirmation emails to mailing list members). Is there any way that "allow open subscribe" can be enabled so this can be used?

To answer the first question regarding double-opt in mailing lists, I don't want confirmations sent to mailing list members because this approval/confirmation is managed through the custom (password protected) website directly.

This mailing list is used as an announment only type mailing list - and I think they probably have no more than 300 emails on the list at last check. And no, they don't want to use PHPList or the like, because they like being able to send emails directly to an email address rather than log in to another software program.

Thanks,
Nathan