[evolution-data-server] I#82 - Use uppercase in MIME-Version 1.0 header

[Milan Crha <mcrha src gnome org>]

commit 695a9f429a18a2bac72a1526d1498124b952ad80
Author: Milan Crha <mcrha redhat com>
Date:   Tue Jan 29 18:10:56 2019 +0100

    I#82 - Use uppercase in MIME-Version 1.0 header
    
    Closes https://gitlab.gnome.org/GNOME/evolution-data-server/issues/82

 src/camel/camel-mime-message.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/src/camel/camel-mime-message.c b/src/camel/camel-mime-message.c
index ee8093e72..eb9173f84 100644
--- a/src/camel/camel-mime-message.c
+++ b/src/camel/camel-mime-message.c
@@ -212,8 +212,10 @@ mime_message_ensure_required_headers (CamelMimeMessage *message)
 
        /* FIXME: "To" header needs to be set explicitly as well ... */
 
-       if (!camel_medium_get_header (medium, "Mime-Version"))
-               camel_medium_set_header (medium, "Mime-Version", "1.0");
+       /* Use uppercase MIME, to follow RFC 2045 convention (and to not trigger
+          some spam-detection rules on some servers/clients). */
+       if (!camel_medium_get_header (medium, "MIME-Version"))
+               camel_medium_set_header (medium, "MIME-Version", "1.0");
 }
 
 static void