Early last year some folks started finding clues that Google was building offline support for Google Calendar. Now it looks like the company is finally rolling out that feature.

Mark Mathson of Keenpath noticed an offline access button in his Google Calendar yesterday. As you would expect, the service uses Google Gears, which means you'll need to either install Gears for Firefox or Internet Explorer or use Google Chrome, which has it built in.

The feature isn't available for all users yet. But Google seems to be adding it to Google Apps user accounts first, which is unusual since the general public often gets access to new features before the Google Apps crowd.

To find out whether Google's ready to let you read your calendar offline, loging to your Google Calendar account and click the settings link. If you see a tab that says offline, you can configure your settings and download the data from Google Calendar to your desktop. This will let you view your calendar when you're not connected to the internet, and even create, delete, and edit appointments. When you connect to the internet again you can synchronize any changes you've made with the server.

Update: Google Calendar will only be available in read-only mode when you're offlinne. That's rather dissapointing.

[via Google Operating System]