I have a @yahoo.co.uk email address. When I have gone through Yahoo Mail! Account Setup in Zimbra Desktop i get the message "Service error. Please check your server settings; verify your email address, password or IMAP access (if required)."

However if I enter my yahoo mail address as a @yahoo.com instead of @yahoo.co.uk I get logged in and can see my email. However, I cannot send as mail just sits it the outbox, even after pressing the send/receive button. Is this a bug with the software, a problem on the Yahoo Mail end or am I doing something wrong?