diff --git a/composer.json b/composer.json
index 0ab8f5110..8e78ab394 100644
--- a/composer.json
+++ b/composer.json
@@ -1,5 +1,6 @@
 {
     "require" : {
+        "php": ">=5.3",
         "ext-mbstring" : "*",
         "fguillot/simple-validator" : "dev-master",
         "swiftmailer/swiftmailer" : "@stable",
@@ -24,4 +25,4 @@
     "require-dev" : {
         "symfony/stopwatch" : "~2.6"
     }
-}
\ No newline at end of file
+}