Re: New mail popup
What popup are you talking about? The only mail-related popups I can think of are the ones that ask you to confirm taking a COD item (and sending the requested money amount).
Re: Trade popup
Not possible. Accepting a trade requires a hardware action (click or keypress); an addon cannot do it automatically See the "Things Addons/Macros Can't Do" sticky thread in the Addon Search/Requests forum (which is where your post should be, since you're looking for a new addon, not asking for help with an existing addon):
http://www.wowinterface.com/forums/s...ad.php?t=42367