We're running Zimbra 5.02. it has been running fine for over a month. Then today at about 3:30pm the web client slowed to a crawl. Logging in now takes about 10 minutes and even if you do get logged in you can't do anything except logout. Everything else results in a "Server busy" or some such error. I've tried from different PC's and with different clients, and all are acting the same.
The weird part is that the Administration web client works just fine. Also all POP and IMAP clients are also working fine.