How to treat disabled Mailing lists?

Each list cab be disabled by an admin. If a list is disabled then no mail is sent to a list. The mail wil be sent after the admin enables the list again.

How should we handle sending mail _to_ the list?

1) Bounce all incoming mail back to the sender?
2) Store incoming mail and process it when the list is enabled again?
3) just accept the mail (current situation).
4) Silently discard incoming mail.