Added required mail.smtp.auth property

git-svn-id: http://scm.dspace.org/svn/repo/trunk@1378 9c30dcfa-912a-0410-8fc2-9e0234be79fd

dspace/src/org/dspace/core/Email.java

@@ -265,6 +265,7 @@ public class Email
         
         if (username != null)
         {
+            props.put("mail.smtp.auth", "true");
             SMTPAuthenticator smtpAuthenticator = new SMTPAuthenticator(
                     username, password);
             session = Session.getDefaultInstance(props, smtpAuthenticator);