diff --git a/src/Server.php b/src/Server.php
index 9746184..6238db7 100644
--- a/src/Server.php
+++ b/src/Server.php
@@ -598,7 +598,7 @@ protected static function isSubclassOf($className, $type)
         if (is_subclass_of($className, $type)) {
             return true;
         }
-        if (version_compare(PHP_VERSION, '5.3.7', '>=')) {
+        if (PHP_VERSION_ID >= 50307) {
             return false;
         }
         if (!interface_exists($type)) {