[Evolution] pop server usage question

["Matthew J. Doller" <mdoller wpi edu>]

i'm using evolution to access a pop account of mine.  it's set up to
check for new mail every 5 minutes, and to leave the messages on the
server.
recently i got an e-mail from my administrator saying that over the
course of a day, i had accessed over 700 megs of mail over the course of
a day.
well, my inbox was pretty big, but not 700 megs big.
so, my question is this:
how does evolution check for new mail on a pop server?  does it download
all of the mail, and then check locally, or does it just download the
new/unread mail.  it would seem that it's doing the former, but maybe 
not
if it is downloading all the mail, what's the reason for that?  

thanks
matt

ps - this occurred on a nightly from about 2 weeks ago.  if the handling
of pop mail has changed, sorry for the inbox clutter

-- 
Matthew J. Doller 
mdoller wpi edu
http://www.wpi.edu/~mdoller