#1 : Thunderbird uses wrong character encoding¶

When I send to myself a message containing a single line of text “Liebe Grüße”, then the message is displayed correctly in my inbox. But when I hit Ctrl-R, then the encoding gets mixed up:

On 14/01/14 13:57, Luc Saffre wrote:
> Liebe GrÃ¼ÃŸe
>

The same happens with Ctrl-E (edit as new)