diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
index 6b08399f3d..73473cf3f8 100644
--- a/src/Symfony/Component/HttpKernel/Kernel.php
+++ b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -730,17 +730,26 @@ abstract class Kernel implements KernelInterface, TerminableInterface
             return $source;
         }
 
+        $rawChunk = '';
         $output = '';
-        foreach (token_get_all($source) as $token) {
+        $tokens = token_get_all($source);
+        for (reset($tokens); false !== $token = current($tokens); next($tokens)) {
             if (is_string($token)) {
-                $output .= $token;
+                $rawChunk .= $token;
+            } elseif (T_START_HEREDOC === $token[0]) {
+                $output .= preg_replace(array('/\s+$/Sm', '/\n+/S'), "\n", $rawChunk) . $token[1];
+                do {
+                    $token = next($tokens);
+                    $output .= $token[1];
+                } while ($token[0] !== T_END_HEREDOC);
+                $rawChunk = '';
             } elseif (!in_array($token[0], array(T_COMMENT, T_DOC_COMMENT))) {
-                $output .= $token[1];
+                $rawChunk .= $token[1];
             }
         }
 
         // replace multiple new lines with a single newline
-        $output = preg_replace(array('/\s+$/Sm', '/\n+/S'), "\n", $output);
+        $output .= preg_replace(array('/\s+$/Sm', '/\n+/S'), "\n", $rawChunk);
 
         return $output;
     }
diff --git a/src/Symfony/Component/HttpKernel/Tests/KernelTest.php b/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
index 46361f6f5a..d4295f5ab8 100644
--- a/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
@@ -223,9 +223,28 @@ class KernelTest extends \PHPUnit_Framework_TestCase
 
             return;
         }
-        $source = <<<EOF
+        $source = <<<'EOF'
 <?php
 
+$string = 'string should not be   modified';
+
+
+$heredoc = <<<HD
+
+
+Heredoc should not be   modified
+
+
+HD;
+
+$nowdoc = <<<'ND'
+
+
+Nowdoc should not be   modified
+
+
+ND;
+
 /**
  * some class comments to strip
  */
@@ -240,8 +259,25 @@ class TestClass
     }
 }
 EOF;
-        $expected = <<<EOF
+        $expected = <<<'EOF'
 <?php
+$string = 'string should not be   modified';
+$heredoc =
+<<<HD
+
+
+Heredoc should not be   modified
+
+
+HD;
+$nowdoc =
+<<<'ND'
+
+
+Nowdoc should not be   modified
+
+
+ND;
 class TestClass
 {
     public function doStuff()