I have quite a few people in my unit that I need to keep in sync. So, I set up a calendar on my exchange account and shared it. That went fine for a while and was picked up on the iPad with no trouble. But, then a couple of people needed to be added with older Macs, and the calendar I had created (something about being created on a PC) wouldn't work. So, our IT division set up a calendar outside of any of our accounts, but added everyone as delegates, with me as "owner."
I was able to help everyone get the calendar working on PCs with Outlook, and Mac desk/laptops with Entourage or iCal. I have not been able to get the calendar to show up on anything with IOS5. The delegates option doesn't exist on those. I am trying to get IT to share a full link (they have been confused about how to do that) to see if opening it on the iPad will create a connection with the calendar.