diff --git a/configure.ac b/configure.ac
index c600ae161..06b33741f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -161,6 +161,7 @@ AC_CHECK_FUNCS([\
 	setreuid statfs sysconf \
 	tcgetattr tcsetattr truncate \
 	strverscmp \
+	strncasecmp \
 	realpath
 ])
 
diff --git a/lib/strutil/strutil8bit.c b/lib/strutil/strutil8bit.c
index f8a934fc0..644f3555d 100644
--- a/lib/strutil/strutil8bit.c
+++ b/lib/strutil/strutil8bit.c
@@ -574,6 +574,24 @@ str_8bit_release_search_needle (char *needle, int case_sen)
     (void) needle;
 }
 
+static char *
+str_8bit_strdown (const char *str)
+{
+    char *rets;
+
+    rets = g_strdup (str);
+    if (rets == NULL)
+        return NULL;
+
+    while (*rets != '\0')
+    {
+        *rets = char_tolower (*rets);
+        rets++;
+    }
+    return rets;
+}
+
+
 static const char *
 str_8bit_search_first (const char *text, const char *search, int case_sen)
 {
@@ -582,8 +600,8 @@ str_8bit_search_first (const char *text, const char *search, int case_sen)
     const char *match;
     size_t offsset;
 
-    fold_text = (case_sen) ? (char *) text : g_strdown (g_strdup (text));
-    fold_search = (case_sen) ? (char *) search : g_strdown (g_strdup (search));
+    fold_text = (case_sen) ? (char *) text : str_8bit_strdown (text);
+    fold_search = (case_sen) ? (char *) search : str_8bit_strdown (search);
 
     match = g_strstr_len (fold_text, -1, fold_search);
     if (match != NULL)
@@ -609,8 +627,8 @@ str_8bit_search_last (const char *text, const char *search, int case_sen)
     const char *match;
     size_t offsset;
 
-    fold_text = (case_sen) ? (char *) text : g_strdown (g_strdup (text));
-    fold_search = (case_sen) ? (char *) search : g_strdown (g_strdup (search));
+    fold_text = (case_sen) ? (char *) text : str_8bit_strdown (text);
+    fold_search = (case_sen) ? (char *) search : str_8bit_strdown (search);
 
     match = g_strrstr_len (fold_text, -1, fold_search);
     if (match != NULL)
@@ -641,15 +659,74 @@ str_8bit_ncompare (const char *t1, const char *t2)
 }
 
 static int
-str_8bit_casecmp (const char *t1, const char *t2)
+str_8bit_casecmp (const char *s1, const char *s2)
 {
-    return g_strcasecmp (t1, t2);
+    /* code from GLib */
+
+#ifdef HAVE_STRCASECMP
+    g_return_val_if_fail (s1 != NULL, 0);
+    g_return_val_if_fail (s2 != NULL, 0);
+
+    return strcasecmp (s1, s2);
+#else
+    gint c1, c2;
+
+    g_return_val_if_fail (s1 != NULL, 0);
+    g_return_val_if_fail (s2 != NULL, 0);
+
+    while (*s1 != '\0' && *s2 != '\0')
+    {
+        /* According to A. Cox, some platforms have islower's that
+         * don't work right on non-uppercase
+         */
+        c1 = isupper ((guchar) *s1) ? tolower ((guchar) *s1) : *s1;
+        c2 = isupper ((guchar) *s2) ? tolower ((guchar) *s2) : *s2;
+        if (c1 != c2)
+            return (c1 - c2);
+        s1++;
+        s2++;
+    }
+
+    return (((gint)(guchar) *s1) - ((gint)(guchar) *s2));
+#endif
 }
 
 static int
-str_8bit_ncasecmp (const char *t1, const char *t2)
+str_8bit_ncasecmp (const char *s1, const char *s2)
 {
-    return g_strncasecmp (t1, t2, min (strlen (t1), strlen (t2)));
+    size_t n;
+
+    g_return_val_if_fail (s1 != NULL, 0);
+    g_return_val_if_fail (s2 != NULL, 0);
+
+    n = min (strlen (s1), strlen (s2));
+
+    /* code from GLib */
+
+#ifdef HAVE_STRNCASECMP
+    return strncasecmp (s1, s2, n);
+#else
+    gint c1, c2;
+
+    while (n != 0 && *s1 != '\0' && *s2 != '\0')
+    {
+        n -= 1;
+        /* According to A. Cox, some platforms have islower's that
+         * don't work right on non-uppercase
+         */
+        c1 = isupper ((guchar) *s1) ? tolower ((guchar) *s1) : *s1;
+        c2 = isupper ((guchar) *s2) ? tolower ((guchar) *s2) : *s2;
+        if (c1 != c2)
+            return (c1 - c2);
+        s1++;
+        s2++;
+    }
+
+    if (n != 0)
+        return (((gint) (guchar) *s1) - ((gint) (guchar) *s2));
+    else
+        return 0;
+#endif
 }
 
 static int
@@ -681,7 +758,7 @@ str_8bit_fix_string (char *text)
 static char *
 str_8bit_create_key (const char *text, int case_sen)
 {
-    return (case_sen) ? (char *) text : g_strdown (g_strdup (text));
+    return (case_sen) ? (char *) text : str_8bit_strdown (text);
 }
 
 static int
diff --git a/lib/vfs/mc-vfs/ftpfs.c b/lib/vfs/mc-vfs/ftpfs.c
index 502010424..7f5050fae 100644
--- a/lib/vfs/mc-vfs/ftpfs.c
+++ b/lib/vfs/mc-vfs/ftpfs.c
@@ -535,8 +535,12 @@ ftpfs_login_server (struct vfs_class *me, struct vfs_s_super *super, const char
 
     if (ftpfs_get_reply (me, SUP.sock, reply_string, sizeof (reply_string) - 1) == COMPLETE)
     {
-        g_strup (reply_string);
-        SUP.remote_is_amiga = strstr (reply_string, "AMIGA") != 0;
+        char *reply_up;
+
+        reply_up = g_ascii_strup (reply_string, -1);
+        SUP.remote_is_amiga = strstr (reply_up, "AMIGA") != 0;
+        g_free (reply_up);
+
         if (MEDATA->logfile)
         {
             fprintf (MEDATA->logfile, "MC -- remote_is_amiga =  %d\n", SUP.remote_is_amiga);
@@ -682,7 +686,7 @@ ftpfs_check_proxy (const char *host)
             if (!ld)
                 return 0;
         }
-        else if (!g_strcasecmp (host, domain))
+        else if (g_ascii_strcasecmp (host, domain) == 0)
             return 0;
     }
 
@@ -2153,7 +2157,7 @@ ftpfs_find_machine (const char *host, const char *domain)
         if (ftpfs_netrc_next () == NETRC_NONE)
             break;
 
-        if (g_strcasecmp (host, buffer))
+        if (g_ascii_strcasecmp (host, buffer) != 0)
         {
             /* Try adding our domain to short names in .netrc */
             const char *host_domain = strchr (host, '.');
@@ -2161,11 +2165,11 @@ ftpfs_find_machine (const char *host, const char *domain)
                 continue;
 
             /* Compare domain part */
-            if (g_strcasecmp (host_domain, domain))
+            if (g_ascii_strcasecmp (host_domain, domain) != 0)
                 continue;
 
             /* Compare local part */
-            if (g_strncasecmp (host, buffer, host_domain - host))
+            if (g_ascii_strncasecmp (host, buffer, host_domain - host) != 0)
                 continue;
         }
 
diff --git a/src/editor/edit.c b/src/editor/edit.c
index faa9dc98d..2a74599ec 100644
--- a/src/editor/edit.c
+++ b/src/editor/edit.c
@@ -330,14 +330,16 @@ edit_load_file_fast (WEdit * edit, const char *filename)
 
     edit->curs2 = edit->last_byte;
     buf2 = edit->curs2 >> S_EDIT_BUF_SIZE;
+    edit->utf8 = 0;
 
     file = mc_open (filename, O_RDONLY | O_BINARY);
     if (file == -1)
     {
-        GString *errmsg = g_string_new (NULL);
-        g_string_sprintf (errmsg, _("Cannot open %s for reading"), filename);
-        edit_error_dialog (_("Error"), get_sys_error (errmsg->str));
-        g_string_free (errmsg, TRUE);
+        gchar *errmsg;
+
+        errmsg = g_strdup_printf (_("Cannot open %s for reading"), filename);
+        edit_error_dialog (_("Error"), errmsg);
+        g_free (errmsg);
         return 1;
     }
 
@@ -627,7 +629,7 @@ static int
 check_file_access (WEdit * edit, const char *filename, struct stat *st)
 {
     int file;
-    GString *errmsg = (GString *) 0;
+    gchar *errmsg = NULL;
 
     /* Try opening an existing file */
     file = mc_open (filename, O_NONBLOCK | O_RDONLY | O_BINARY, 0666);
@@ -635,14 +637,13 @@ check_file_access (WEdit * edit, const char *filename, struct stat *st)
     if (file < 0)
     {
         /*
-         * Try creating the file.  O_EXCL prevents following broken links
+         * Try creating the file. O_EXCL prevents following broken links
          * and opening existing files.
          */
         file = mc_open (filename, O_NONBLOCK | O_RDONLY | O_BINARY | O_CREAT | O_EXCL, 0666);
         if (file < 0)
         {
-            g_string_sprintf (errmsg = g_string_new (NULL),
-                              _("Cannot open %s for reading"), filename);
+            errmsg = g_strdup_printf (_("Cannot open %s for reading"), filename);
             goto cleanup;
         }
         else
@@ -655,15 +656,14 @@ check_file_access (WEdit * edit, const char *filename, struct stat *st)
     /* Check what we have opened */
     if (mc_fstat (file, st) < 0)
     {
-        g_string_sprintf (errmsg = g_string_new (NULL),
-                          _("Cannot get size/permissions for %s"), filename);
+        errmsg = g_strdup_printf (_("Cannot get size/permissions for %s"), filename);
         goto cleanup;
     }
 
     /* We want to open regular files only */
     if (!S_ISREG (st->st_mode))
     {
-        g_string_sprintf (errmsg = g_string_new (NULL), _("\"%s\" is not a regular file"), filename);
+        errmsg = g_strdup_printf (_("\"%s\" is not a regular file"), filename);
         goto cleanup;
     }
 
@@ -672,21 +672,18 @@ check_file_access (WEdit * edit, const char *filename, struct stat *st)
      * O_EXCL should prevent it, but let's be on the safe side.
      */
     if (st->st_size > 0)
-    {
         edit->delete_file = 0;
-    }
 
     if (st->st_size >= SIZE_LIMIT)
-    {
-        g_string_sprintf (errmsg = g_string_new (NULL), _("File \"%s\" is too large"), filename);
-    }
+        errmsg = g_strdup_printf (_("File \"%s\" is too large"), filename);
 
   cleanup:
     (void) mc_close (file);
-    if (errmsg)
+
+    if (errmsg != NULL)
     {
-        edit_error_dialog (_("Error"), errmsg->str);
-        g_string_free (errmsg, TRUE);
+        edit_error_dialog (_("Error"), errmsg);
+        g_free (errmsg);
         return 1;
     }
     return 0;
diff --git a/src/editor/syntax.c b/src/editor/syntax.c
index a3f24b534..bbd6f2fa2 100644
--- a/src/editor/syntax.c
+++ b/src/editor/syntax.c
@@ -134,7 +134,7 @@ mc_defines_destroy (gpointer key, gpointer value, gpointer data)
 static void
 destroy_defines (GTree ** defines)
 {
-    g_tree_traverse (*defines, mc_defines_destroy, G_POST_ORDER, NULL);
+    g_tree_foreach (*defines, mc_defines_destroy, NULL);
     g_tree_destroy (*defines);
     *defines = NULL;
 }
diff --git a/src/setup.c b/src/setup.c
index f6dc1d70f..7e0c0c584 100644
--- a/src/setup.c
+++ b/src/setup.c
@@ -485,7 +485,7 @@ load_keys_from_section (const char *terminal, mc_config_t * cfg)
     while (*profile_keys != NULL)
     {
         /* copy=other causes all keys from [terminal:other] to be loaded. */
-        if (g_strcasecmp (*profile_keys, "copy") == 0)
+        if (g_ascii_strcasecmp (*profile_keys, "copy") == 0)
         {
             valcopy = mc_config_get_string (cfg, section_name, *profile_keys, "");
             load_keys_from_section (valcopy, cfg);
@@ -647,7 +647,7 @@ setup__load_panel_state (const char *section)
     buffer = mc_config_get_string (mc_panels_config, section, "display", "listing");
 
     for (i = 0; panel_types[i].opt_name != NULL; i++)
-        if (g_strcasecmp (panel_types[i].opt_name, buffer) == 0)
+        if (g_ascii_strcasecmp (panel_types[i].opt_name, buffer) == 0)
         {
             mode = panel_types[i].opt_type;
             break;
@@ -1123,7 +1123,7 @@ panel_load_setup (WPanel * panel, const char *section)
     buffer = mc_config_get_string (mc_panels_config, section, "list_mode", "full");
     panel->list_type = list_full;
     for (i = 0; list_types[i].key != NULL; i++)
-        if (g_strcasecmp (list_types[i].key, buffer) == 0)
+        if (g_ascii_strcasecmp (list_types[i].key, buffer) == 0)
         {
             panel->list_type = list_types[i].list_type;
             break;