diff --git a/inc/config.php b/inc/config.php
index 1fd00a3d..6f2371ec 100644
--- a/inc/config.php
+++ b/inc/config.php
@@ -381,10 +381,10 @@
  */
 
 	// "Wiki" markup syntax ($config['wiki_markup'] in pervious versions):
-	$config['markup'][] = array("/'''(.+?)'''/", "<strong>\$1</strong>");
-	$config['markup'][] = array("/''(.+?)''/", "<em>\$1</em>");
-	$config['markup'][] = array("/\*\*(.+?)\*\*/", "<span class=\"spoiler\">\$1</span>");
-	$config['markup'][] = array("/^[ |\t]*==(.+?)==[ |\t]*$/m", "<span class=\"heading\">\$1</span>");
+	$config['markup'][] = array("/'''([^<]+?)'''/", "<strong>\$1</strong>");
+	$config['markup'][] = array("/''([^<]+?)''/", "<em>\$1</em>");
+	$config['markup'][] = array("/\*\*([^<]+?)\*\*/", "<span class=\"spoiler\">\$1</span>");
+	$config['markup'][] = array("/^[ |\t]*==([^<]+?)==[ |\t]*$/m", "<span class=\"heading\">\$1</span>");
 	
 	// Highlight PHP code wrapped in <code> tags (PHP 5.3.0+)
 	// $config['markup'][] = array(