I use Google's calendar and can view it from Calendar (previously iCal) on my Mac. However, Google's calendar either sends me a SMS text message or an email, or both, depending on how I have my alert set up for the specific event. Before upgrading to Mountail Lion, iCal suddenly started launching Mail.app to send me an additional alert email. I turned that off in iCal. Now with Mountain Lion, the behavior is back, but there's no equivalent setting in Calendar to turn off. How do I stop Mountain Lion from using Mail.app to send me alerts for Calendar events?
MacBook Pro, OS X Mountain Lion, iPhone OS 5.1.1