https://pear.php.net/bugs/bug.php?id=23775
--- a/Mail/mimeDecode.php
+++ b/Mail/mimeDecode.php
@@ -834,7 +834,7 @@
 
         // Replace encoded characters
 		 
-        $cb = create_function('$matches',  ' return chr(hexdec($matches[0]));');
+        $cb = function($matches) { return chr(hexdec($matches[0])); };
          
         $input = preg_replace_callback( '/=([a-f0-9]{2})/i', $cb, $input);