I have successfully set the GMAIL SMTP over SSL for my moodle site. The site offers Self Registration for Students and mails being shoot to their given email ID for account activation purpose.
These mails are properly being sent if the number of concurrent / parallel registration is less (below 10). But, if more than 12-15 students are parallely getting themselves registered in this portal, the GMAIL SMTP is throwing SMTP Connect() failed error after each 12-15 mails. We need to wait for nearly 10 minutes to again have the SMTP back operational.
Is there any limit set for this time lag .. please note that the "SMTP Session Limit" is set to 100 in the portal's outgoing mail configuration window.