Ehh... It has a plugin that lets you run their web client from within Thunderbird. To me that doesn't really count, but maybe it does for you and all power to you if so.
Edit: Typo
Ehh... It has a plugin that lets you run their web client from within Thunderbird. To me that doesn't really count, but maybe it does for you and all power to you if so.
Edit: Typo