When clients send an email through smtp protocol for commerce, an exception is recorded in the trace, saying "Protocol 'smtps' is not used with user authentication".
In the trace, there is an exception as shown below:
[7/30/13 16:24:07:344 CST] 000000c4 jcaemail 3 com.ibm.commerce.messaging.adapters.jcaemail.JCAEmailConnectionRequestInfo getCsProps() Protocol 'smtps' is not used with user authentication. The socket factory may need to be updated.
It is caused by the "username" and "password" that is passed in as authenticator, then OOB uses SSL socket to send the mail.
Resolving the problem
When customers send an email through SMTP protocol for commerce, it is recommend that "username" and "password" be removed when sending the mail through SMTP. This is because using non-SSL with user authentication may potentially expose username/password in communication to the SMTP server.
If the client has a strong requirement to send mail with username/password, they can add the line "mail.smtp.socketFactory.class=javax.net.SocketFactory" into the JCAEmailConnectionRequestInfo.properties. And, if they also do not want to use TLS-protected connection in such scenario, they should also add "mail.smtp.starttls.enable=false".