diff --git a/lib/php/src/Thrift.php b/lib/php/src/Thrift.php
index 4fe4392..0364c90 100644
--- a/lib/php/src/Thrift.php
+++ b/lib/php/src/Thrift.php
@@ -82,7 +82,7 @@
         }
       }
     } else {
-      parent::__construct($p1, $p2);
+      parent::__construct((string)$p1, $p2);
     }
   }