User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7 Build Identifier: It would be useful to have multiple SMTP servers associated with an account or identity and have TB automatically try the next SMTP server in the list on a failure to send an email (be that a temporary connection issue or some other issue that causes an error when sending email) One scenario would be having different SMTP servers for different ISP's. Currently one has to change the SMTP for an account manually or select an Identity manually. Reproducible: Always