This seems to occur for me too. Create a new item in Lightning and it will appear twice in Outlook. Thunderbird will only show one item.
Thunderbird 3.1.9 Lightning 1.0b2 Exchange provider 0.12 Windows 7 x64
This seems to occur for me too.
Create a new item in Lightning and it will appear twice in Outlook.
Thunderbird will only show one item.
Thunderbird 3.1.9
Lightning 1.0b2
Exchange provider 0.12
Windows 7 x64