Being a Drupal developer I do use magnificent redmine (http://redmine.org) to manage my tasks and projects. If you don't know, Redmine is a Rails-based application so from time to time I have my hands dirty with ruby code (it doesn't hurt at all ;)).
Today I decided to upgrade our internal redmine installation from version 1.4 to 2.0. The upgrade process went very smooth, but in the end I encountered a problem with mail sending. Every attempt to send an email from redmine installation led to the error message: An error occurred while sending mail (SSL_connect returned=1 errno=0 state=unknown state: unknown protocol). I use Google Apps SMTP servers for mail, so my configuration file looked something like this: