I dont understand how to implement the bounce email settings

Hi there - I am using the e-newsletter plugin and its great however, I am a bit in the dark about how the bounced email component works. It says something about needing a seperate email account setup with smtp in order to work?

I am already using a gmail account with smtp to deliver the newsletter - do I need to set up a different one to manage the bounces?

How do the bounced emails get handled by the wordpress system - are those users not sent an email next time around until their email is "resolved"?

Those few answers would really help clarify.