Thanks for the link! In addressing the original issue of this thread, it appears Apple may have moved its former mac.com addresses over and that many of the calendars we were previously using with mac.com addresses may be available again by going to the Help menu in iCal and choosing the "Find Calendar Subscriptions..." to take you to the Apple site. This is good news.
The link you provided is very much appreciated. I only found some very basic Islamic holidays, such as the end of Ramadan and the Islamic New Year. I will continue my search for a more detailed calendar since I have students that may be celebrating such holidays and I'd like to know when/if they may need time off.
Also--last I checked, Islam is a religion--not a nationality. Finland is a country. Islam is not. People in America practice Islam and it's not "politically correct" to say so. It's simply a fact. I would hope you would like to learn more and not just dismiss it as political correctness, but as an awareness of something other than your point of view. Here's a good place to start. Note # 1 in the article.
http://www.washingtonpost.com/opinions/five-myths-about-muslims-in-america/2011/ 03/30/AFePWOIC_story.html
I wish you a blessed day as well.