On 2.5.2014, at 11.27, Atsuko Tanaka <tan...@designet.co.jp> wrote: > We have currently set dovecot.sieve to insert the text "[SPAM]" at the > beginning of an e-mail's subject when it's X-Spam-Score is above 80%. > After we set our system as stated the following errors occur: > > 1) When an e-mail's subject contains control characters like > [Ctrl+V|^V], dovecot.sieve terminates with an error and an e-mail is not > able to be sent. When a MIME encoded Subject like [ＴＥＳＴ^VＭＡＩＬ] is sent > we're not able to edit the subject and dovecot ends with an error. .. > Aside from [Ctrl + V] the following control charcters also cause errors: > backspace > Ctrl + A > Ctrl + C > Ctrl + [ > Ctrl + X > Ctrl + Y > > 2) When an e-mail's subject line contains a "\0" character, everything > following the null character is deleted.
Is there a reason why mails contain these kind of control characters? Is it commonly used? And is it OK if Dovecot translates them to UTF-8 for the rewritten header, or would the subject have to stay ISO-2022-JP encoded?
