--- mutt/init.h.orig	2016-04-09 11:37:12.650818818 +0200
+++ mutt/init.h	2016-04-09 11:57:47.378726695 +0200
@@ -873,6 +873,11 @@
   ** message via mail.
   */
 #endif
+   { "force_base64",   DT_BOOL, R_NONE, OPTFORCEBASE64, 0 },
+   /*
+   ** .pp
+   ** If you need to encode all text parts to base64, set this option.
+   */
   { "force_name",	DT_BOOL, R_NONE, OPTFORCENAME, 0 },
   /*
   ** .pp
--- mutt-1.5.24-orig/mutt.h    2015-08-30 19:06:38.000000000 +0200
+++ mutt-1.5.24/mutt.h 2016-02-09 13:48:24.758051324 +0100
@@ -339,6 +339,7 @@ enum
   OPTFASTREPLY,
   OPTFCCCLEAR,
   OPTFOLLOWUPTO,
+  OPTFORCEBASE64,
   OPTFORCENAME,
   OPTFORWDECODE,
   OPTFORWQUOTE,
--- mutt-1.5.24-orig/sendlib.c 2015-08-30 19:06:38.000000000 +0200
+++ mutt-1.5.24/sendlib.c      2016-02-09 13:48:24.759051309 +0100
@@ -1168,7 +1168,9 @@ static void mutt_set_encoding (BODY *b,
   if (b->type == TYPETEXT)
   {
     char *chsname = mutt_get_body_charset (send_charset, sizeof (send_charset), b);
-    if ((info->lobin && ascii_strncasecmp (chsname, "iso-2022", 8)) || info->linemax > 990 || (info->from && option (OPTENCODEFROM)))
+    if (option (OPTFORCEBASE64))
+      b->encoding = ENCBASE64;
+    else if ((info->lobin && ascii_strncasecmp (chsname, "iso-2022", 8)) || info->linemax > 990 || (info->from && option (OPTENCODEFROM)))
       b->encoding = ENCQUOTEDPRINTABLE;
     else if (info->hibin)
       b->encoding = option (OPTALLOW8BIT) ? ENC8BIT : ENCQUOTEDPRINTABLE;