[Plugin: Mailpress] How to enter emails manually without subscribing?

Hello there,

I’ve installed mailpress as the mailing module for sending out weekly/monthly for my blogs subscribers. Now the problem is that, there are few emails that i wish to add to the mailpress mailing list manually (without them actually subscribing). I have checked, but there seems to be no option to add email addresses manually by the admin.

Is this actually possible? If it is not possible, can someone kindly recommend me another free mailing plugin (newsletter + monthly posts)that i should check out which has this feature?

Thanks in advance.