diff -rup mutt-17a4f92e4a95-orig/init.h mutt-17a4f92e4a95-new/init.h
--- mutt-17a4f92e4a95-orig/init.h	2015-06-07 22:59:32.000000000 +0200
+++ mutt-17a4f92e4a95-new/init.h	2015-06-25 15:28:56.095570332 +0200
@@ -2989,7 +2989,7 @@ struct option_t MuttVars[] = {
   */
 #if defined(USE_SSL)
 #ifdef USE_SSL_GNUTLS
-  { "ssl_ca_certificates_file", DT_PATH, R_NONE, UL &SslCACertFile, 0 },
+  { "ssl_ca_certificates_file", DT_PATH, R_NONE, UL &SslCACertFile, "/etc/ssl/certs/ca-bundle.crt" },
   /*
   ** .pp
   ** This variable specifies a file containing trusted CA certificates.