can't change SMTP server

I would like to change my SMTP server from smtp.aol.com to 
smtp.att.yahoo.com  After going to edit...mail and newsgroup account 
settings and changing the outgoing SMTP server, and clicking OK, when I 
attempt to send Email, it still attempts to connect to smtp.aol.com and 
fails.

Any clues as to what is going wrong and how I can fix it?

Jose
-- 
You can choose whom to befriend, but you cannot choose whom to love.
for Email, make the obvious change in the address.