mutt/2173: When replying to a message, Mutt should filter control characters from headers

[vincent@xxxxxxxxxx]

>Number:         2173
>Notify-List:    
>Category:       mutt
>Synopsis:       When replying to a message, Mutt should filter control 
>characters from headers
>Confidential:   no
>Severity:       normal
>Priority:       medium
>Responsible:    mutt-dev
>State:          open
>Keywords:       
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 30 11:20:04 +0100 2006
>Originator:     Vincent Lefevre
>Release:        cvs + patches
>Organization:
>Environment:
>Description:
I received a message from a broken MUA (JavaMail) containing (I simplified a 
bit):

Subject: =?UTF-8?Q?Echangez_votre_ordinateur_contre_un?=
 =?UTF-8?Q?_...processe=0D=0Aur_Intel_?=

When replying to this message with $edit_headers set, I got in the editor:

Subject: Re: Echangez votre ordinateur contre un ...processe
^M
ur Intel 

i.e. invalid headers since a wrapped line must start with either a space or a 
tab character. Mutt should filter out control and non-printable characters.
>How-To-Repeat:
>Fix:
Unknown
>Add-To-Audit-Trail:

>Unformatted: