fyi:
QuoteAs of Tuesday, May 24, 2011, users will no longer be able to use Chrome with Google Gears-based Gmail Offline. The Offline setting will not appear in the Settings menu, and users may receive an error message when they try to access their Gmail offline.
Any messages placed in user's offline outbox before May 24th, will be automatically sent the next time the user logs into Gmail via Chrome for following few weeks (until the release of the next generation Chrome browser, which doesn't support Gears). However, users cannot view or access their Gmail offline.
Actions to take: We recommend that you notify your users of the change to Gmail Offline and direct them to use one of the following options to continue to access their Gmail offline:
Mozilla Firefox 3.6
Microsoft Internet Explorer 8
IMAP client (such as Thunderbird)
Google Apps Sync for Microsoft Outlook (requires installation of client plug-in)
http://www.google.com/support/a/bin/answer.py?hl=en&answer=1308394 (http://www.google.com/support/a/bin/answer.py?hl=en&answer=1308394)