Binary package “xul-ext-gdata-provider” in ubuntu precise

Calendar Extension for Thunderbird - Google Calendar support

 Lighting is the Mozilla Calendar extension for Thunderbird, based
 on Sunbird - the Mozilla Standalone Calendar application. It is tightly
 integrated with Thunderbird, allowing it to easily perform email-related
 calendaring tasks.
 This package provides Google Calendar support. It's a recommended component
 if you want to connect to your google calendar.