diff --git a/src/Gaufrette/Adapter/Ftp.php b/src/Gaufrette/Adapter/Ftp.php
index d578833e..6cc229ea 100644
--- a/src/Gaufrette/Adapter/Ftp.php
+++ b/src/Gaufrette/Adapter/Ftp.php
@@ -490,6 +490,10 @@ private function computePath($key)
      */
     private function isConnected()
     {
+        if (class_exists('\FTP\Connection')) {
+            return $this->connection instanceof \FTP\Connection;
+        }
+
         return is_resource($this->connection);
     }