I have birthdays saved in Outlook as recurring "All day events" (that recur yearly) and mark then private. The problem is that when I share my calendar, the person just sees "private appointment" that lasts the whole day, when it's just a birthday reminder for me.

Is there a way to indicate that these events so I'm not seen as busy the whole day? Is there a better way to store birthdays?

I'm using Outlook 2010 with Exchange (not sure of the version)