Hum, when I receive a mail for
julien@blabla.com, I want to answer with the identity
'julien@blabla.com'. But when my chief is sending me mail to
julien@myworkadress.com, I want to answer him with the identity
'julien@myworkadress.com'. You understand, I don't want to show my private mail adress to my chief

.
I know that's bad to compare to desktop mail client, but thunderbird or outlook manage that. I think they are getting the destination mail adress, and if it's corresponding to an existing identity, they choose the corresponding identity. If no correspondance is found, they choose the default identity....
Regards,