Google Calendar now supports "CalDAV", a presumably better standard
for remotely shared data. To set up your calendars in Lightning:
1. Go to your online Google Calendar, select "Settings / Calendars /
Share This Calendar", then enter the person's Google Mail e-mail
address you want to share with (I think they must have a Google
Calendar account too).
2. Create a new calendar in Mozilla Calendar, select "CalDAV",
Location =
https://www.google.com/calendar/dav/GOOGLE-EMAIL-ADDRESS-OF-CALENDAR-OWNER'S-ACCOUNT/events
(including the @
gmail.com)
(What if the owner has multiple shared calendars? Which one(s) does
Mozilla Calendar then list?)
3. When signing in to any shared calendar, enter YOUR Google username.
Use your FULL Google e-mail address (incl. @...).
4. If you don't have write access to the shared calendar (from step
1), go to the "Properties" of the Mozilla Calendar (by double-clicking
on the calendar) and select "Read Only".
Full instructions here:
http://www.google.com/support/calendar/bin/answer.py?answer=99358#sunbird
NOTE: If you are referring to an account created in Germany, you must
use @GoogleMail.com and not @GMail.com.