Authentication failed Entourage doesn't support available authentication...

I tried to set up and exchange account through Entourage. It works fine for receiving, but I cannot send through the account, I assume because I do not have a Certificated Authorization. So I tried to create a Certificate, since the help and instructions suggested such. This meant I had to create on in my Keychain.

Well nothing worked, so I decided I would cheat and just create an account to send from Entourage using my exchange email account as an alias. The down side being exchange would not capture the "Sent" messages. Oh Well, I could live with that.

This is when I started getting this error and Entourage would not send the message:

"Authentication failed because Entourage doesn't support any of the available authentication methods."

I eventually learned to go to the Keychain and try to verify the error and repair it. The error that appears on verification is:

"Item “mail.bellsouth.net” has unspecified value for port attribute"

Once the repair is executed, it shows it is repaired, but Entourage will still not send mail. So,...yes there is more...I decided to create an identical account to my working bellsouth account, that still works perfectly by the way, and the new account demonstrates the same problem and will not send, but all settlings are identical to my original POP3/SMTP account.

Help! I do not have time machine running, but that is another issues, so lets see if I can fix this first.

Thanks for whoever can come to the rescue!
BarryCuda