diff --git a/lib/ace/mode/php_highlight_rules.js b/lib/ace/mode/php_highlight_rules.js
index 2841d0e9..dc08198d 100644
--- a/lib/ace/mode/php_highlight_rules.js
+++ b/lib/ace/mode/php_highlight_rules.js
@@ -1045,7 +1045,7 @@ var PhpHighlightRules = function() {
     for (var i in this.$rules) {
         this.$rules[i].unshift({
             token : "support.php_tag", // php open tag
-            regex : "<\\?(?:php|\\=)",
+            regex : "<\\?(?:php|\\=)?",
             next  : "php-start"
         });
     }