Birthdays a day early in Calendar on Mountain Lion On my Macbook Pro running Mac OS X 10.8.2 (Mountain Lion) all the birthdays from the "Birthdays" calendar are showing a day early in Calendar. E.g. When I browse to contact Joe Bloggs in Contacts it shows his birthday as 12/03/1987. When I go into Calendar, there is a full day event for Joe Bloggs' birthday on 11/03/1987.

In Calendar I have selected the correct timezone (New Zealand Time) and have also enabled "Turn on time zone support" in the preferences. On my iPhone, I have the same settings and the birthdays display on the correct date.

Is there anything I can do to get the birthdays to display on the correct date in Calendar on my Macbook Pro?

Edit: Just clarifying, the date format used here is dd/mm/yyyy.
I was having a similar issue for a while using the native Birthday calendar. It's not exactly the same as only the notifications came in one day early. 

To fix this, in macOS El Capitan with Calendar v8.0 (2092.3), I found the following:


Open the Calendar app on macOS
Select Preferences > Alerts
Here change the notification for Birthdays to your choice (in my case "On day of event")


I looked for this option a while ago but was unable to find it earlier. But now with this, I'm neatly notified on the day of a birthday. Perhaps it helps others as well.