i think i found a answers to mu problem. I am able to download all email to one address. So i think i can setup all the user accounts on the remote server and then set fetchmail to retrieve each users email from his remote folder and put it in his local folder. I just hope that it wont slow down my system. The good thing to this solution is that when they send large emails to each other then it wont use up my bandwidth.
What do you think