diff --git a/src/Symfony/Component/Templating/PhpEngine.php b/src/Symfony/Component/Templating/PhpEngine.php
index 6f1c62ef05..f309b6082e 100644
--- a/src/Symfony/Component/Templating/PhpEngine.php
+++ b/src/Symfony/Component/Templating/PhpEngine.php
@@ -38,7 +38,7 @@ class PhpEngine implements EngineInterface, \ArrayAccess
     protected $charset;
     protected $cache;
     protected $escapers;
-    protected $escaperCache;
+    protected static $escaperCache;
     protected $globals;
     protected $parser;
 
@@ -335,14 +335,18 @@ class PhpEngine implements EngineInterface, \ArrayAccess
      */
     public function escape($value, $context = 'html')
     {
+        if (is_numeric($value)) {
+            return $value;
+        }
+
         // If we deal with a scalar value, we can cache the result to increase
         // the performance when the same value is escaped multiple times (e.g. loops)
         if (is_scalar($value)) {
-            if (!isset($this->escaperCache[$context][$value])) {
-                $this->escaperCache[$context][$value] = call_user_func($this->getEscaper($context), $value);
+            if (!isset(self::$escaperCache[$context][$value])) {
+                self::$escaperCache[$context][$value] = call_user_func($this->getEscaper($context), $value);
             }
 
-            return $this->escaperCache[$context][$value];
+            return self::$escaperCache[$context][$value];
         }
 
         return call_user_func($this->getEscaper($context), $value);
@@ -383,7 +387,7 @@ class PhpEngine implements EngineInterface, \ArrayAccess
     public function setEscaper($context, $escaper)
     {
         $this->escapers[$context] = $escaper;
-        $this->escaperCache[$context] = array();
+        self::$escaperCache[$context] = array();
     }
 
     /**
@@ -502,7 +506,7 @@ class PhpEngine implements EngineInterface, \ArrayAccess
                 },
         );
 
-        $this->escaperCache = array();
+        self::$escaperCache = array();
     }
 
     /**