diff --git a/creole.php b/creole.php
index 9383d17..3825c1a 100644
--- a/creole.php
+++ b/creole.php
@@ -490,7 +490,7 @@ function creole($options = array()) {
         for ($i = 1; $i <= 6; $i++) {
             $g['h' . $i] = array(
                 'tag' => 'h' . $i,
-                'regex' => '/(^|\n)[ \t]*={' . $i . '}[ \t]' .
+                'regex' => '/(^|\n)[ \t]*={' . $i . '}[ \t]*' .
                        '([^~]*?(~(.|(?=\n)|$))*)[ \t]*=*\s*(\n|$)/',
                 'capture' => 2
             );