[X4U] Leopard or Snow Leopard Client to Snow Leopard Server email problems?

[Joe Sporleder]

We have a Mac mini running Snow Leopard Server, and since moving mail services from an older Tiger server to the Snow Leopard Server, Mail.app on the Macs has been constantly asking for the POP3 password. I have about 12 users that have accounts on the mini server - one user is running the latest Leopard as a client, the rest are running recent Snow Leopard clients, except for two Windows XP PCs. It's behaving as if there's a timing issue between Mail.app and the Snow Leopard server. Attempts for fresh preferences (Mail and Keychain), clearing out the Keychain and starting fresh, nothing has worked. This problem has affected all of the Macs. One of the Windows PCs running Thunderbird for Windows asked for a password when we first switched over, but has been running great. The other WIndows PC is running Outlook Express or whatever Microsoft's default mail app and it has been running great too since the switch to Snow Leopard Server. Anybody else have authentication problems with Mail.app and a Snow Leopard server? It seems to be a timing issue between Mail.app and the Server, or perhaps it makes me think that the mailbox is busy, and instead of telling me, hey, that account's mailbox is busy, try again later, it instead asks me for the password for the POP3 account. Giving Mail.app the password, or waiting 5-15 minutes usually fixes the problem. Any ideas? Workarounds? Fixes? Is this a server side issue or an issue with the Leopard versions of Mail.app when talking to a Leopard/Snow Leopard server (I had a Leopard server license that I did some testing on and it had the same problem as the Snow Leopard server, but not as severe).

Joe