diff --git a/src/as-utils.c b/src/as-utils.c
index a27860d8..2d91a4db 100644
--- a/src/as-utils.c
+++ b/src/as-utils.c
@@ -2262,6 +2262,7 @@ as_utils_dns_to_rdns (const gchar *url, const gchar *suffix)
 	new_cid = g_string_new (suffix);
 	for (i = 0; parts[i] != NULL; i++) {
 		if (g_strcmp0 (parts[i], "www") != 0) {
+			g_strdelimit (parts[i], "-", '_');
 			g_string_prepend_c (new_cid, '.');
 			g_string_prepend (new_cid, parts[i]);
 		}
diff --git a/tests/test-basics.c b/tests/test-basics.c
index 2feabb45..38f83836 100644
--- a/tests/test-basics.c
+++ b/tests/test-basics.c
@@ -1304,6 +1304,10 @@ test_rdns_convert (void)
 	tmp = as_utils_dns_to_rdns ("https://example.com", "MyApp");
 	g_assert_cmpstr (tmp, ==, "com.example.MyApp");
 	g_free (tmp);
+
+	tmp = as_utils_dns_to_rdns ("https://my-example.org", "My-App");
+	g_assert_cmpstr (tmp, ==, "org.my_example.My-App");
+	g_free (tmp);
 }
 
 /**