[Dovecot] shared folder

Hello list,

I have dovecot-1.2.3 installed on my mail server. I created a shared directory which works fine, however, this shared directory has over 16GB of email and when users, 40 to 50 of them, login to their IMAP account and download of the contents of this shared folder begins on their machines it bogs down the server to a crawl. I had to comment out the share it was so bad. Is there a way to implement permissions on the shared folder and add 1 or 2 users at a time so as not to bog down the server.

Eric Broch