diff --git a/chandler/Signaling/SignalManager.php b/chandler/Signaling/SignalManager.php
index 9522b95..b38793f 100644
--- a/chandler/Signaling/SignalManager.php
+++ b/chandler/Signaling/SignalManager.php
@@ -74,7 +74,7 @@ class SignalManager
             if(!$event) continue;
             
             list($id, $evt) = $event;
-            $id = crc32($id);
+            $id = crc32((string)$id);
             $callback($evt, $id);
         }