Last week I was struggling with fetchmail to catch all mails from a mail box in godaddy and put them in my localhost using fetchmail's multi drop option.
First I tried with a cathcall account which will catch all emails for my domain, but fetchmail was dropping duplicate mails for each cc. and failed to delete the mails in godaddy's mail box also while polling.
At first I thought this was a fetchmail problem, but later on realised the problem was not with fetchmail but with catchall account.
Actually there was no need to create a catchall account, but have to forward each user's mail to a particular account and fetch that account only using fetchmail.
While forwarding each mail like this, the email header will be having one line containing "Delivered-To", which is used by fetchmail to drop the mail in respective mail-box.