diff --git a/src/CachingObjectWrapper.php b/src/CachingObjectWrapper.php
index fdee145..2b99a62 100644
--- a/src/CachingObjectWrapper.php
+++ b/src/CachingObjectWrapper.php
@@ -17,7 +17,7 @@ public function __construct($objectToWrap, CacheItemPoolInterface $cacheItemPool
         $this->expiryInSeconds = $expiryInSeconds;
     }
 
-    public function __call(string $name, array $arguments)
+    public function __call($name, $arguments)
     {
         $cacheKey = sha1(get_class($this->wrappedObject).$name.serialize($arguments));