Probably a stupid question

[Yoshi Melrose]

I have about 10 virtual domains, and they are non-ip based. My question is:
do i have add a user for every email address? i.e. adduser [user] ? Sorry
I'm not *too* familiar with the workings of mail on linux servers. If so,
then my next question is how to handle same names for each domain. How do i
handle multiple webmaster accounts? Thanks for any help!!!

v2kthewebsite
http://www.validus.com
-----
"The Wheel of Time turns, and Ages come and go.
     What was, what will be, and what is,
       may yet fall under the Shadow.
Let the Dragon ride again on the winds of time."
  - The Wheel of Time by Robert Jordan