How do I sync an iCal calendar across Lion, Lepoard, and iOS 5?

My Dad wants to be able to sync his iCal calendar across a Lion MBP, a Leopard MB, and an iPad running iOS 5. Since the Leopard MB doesn't support iCloud, I can't use that. How can I sync an iCal calendar across all these devices?

I've tried to use Google Calendar, but with no success. Maybe it's the way I'm importing it, but I can't get the colors to show up correctly in iCal. When I link iCal to Google Calendar, I want the calendars to look the same in the sidebar. It is a bit confusing with out a screenshot, but I will post a screenshot as soon as I have my Dad's laptop.

I suggest you use Google Calendar (CalDav). You can import these into iCal (both on iPad and Mac). It sync automatically too, so you can have all iCloud-benefits.

I use it with my girlfriend (who is, sadly enough a windows user) and with my company PC. It works like a charm!

I have found a suitable work around that I have been using for a couple of months

While using iCal on a Mac running Snow Leopard, I needed to add an account to iCal. This account would point to iCloud and sync with it.

So, open Preferences and select accounts, enter the add account window by hitting +.

this takes you to:

You need to choose CalDav and enter your Apple ID email address (not your .me.com email address created when you signed up for iCloud)

enter in your password and the server name which in most cases is p06-caldav.icloud.com

Once this has been added you will need to uncheck some of the calendars in the 'on my mac' menu.