I am using Evolution 2.0.2 to retrieve mail from 4 different POP3 accounts on my FC3 machine. When I click the "Send/Receive" button, I see the window with the progress bars (one for each account) and there aren't any error screens or anything. However, when all the mail is apparently done downloading, only new messages in two of the accounts has been retrieved. It's always the same two accounts, and I know the user name and password is correct on all the accounts and I know there is new mail in the accounts.

Anyone know what's going on?

Try to connect through telnet to to pop3 server and see what's going on....

If it helps, Outlook does fine downloading mail simulaneously from 4 accounts, and I can access all the accounts through my ISP's webmail.

I've had a similar prob with one email account and i found a solution by enabling user authentication on smtp....the difference with your case is that i had an error message pop-up saying 'pop3 listing: success" (or sth like that). When i enabled authentication, it worked.
My problem now is that when getting the pop3 listing, it takes too d@mn long...i'll try to find out why, but in the meantime, why don't you try to enable smtp auth yourself and c if u find anything...