diff --git a/composer.json b/composer.json
index 6171717..d1e81e6 100644
--- a/composer.json
+++ b/composer.json
@@ -17,7 +17,7 @@
         }
     ],
     "require": {
-        "php": ">=5.3.0",
+        "php": ">=5.5.0",
         "gregwar/captcha": "~1.1",
         "symfony/framework-bundle": "~2.1",
         "symfony/form": "~2.1"