If you use Google Calendar, Microsoft Outlook, Apple iCal or any other another program that supports the iCalendar format the you can use the webcal address to subscribe to this projects calendar. You can see your tasks as events in the calendar but you need to use Breeze to add or edit tasks.
To subscribe to the calendar:
Google Calendar usually updates webcal calendars only once a day.
Here's a small guide how to import Breeze calendars to Google Calendar.