diff --git a/fbchat/client.py b/fbchat/client.py
index d7b7005..e27706f 100644
--- a/fbchat/client.py
+++ b/fbchat/client.py
@@ -193,7 +193,7 @@ class Client(object):
             'message_batch[0][has_attachment]' : False
         }
 
-        r = self._post("https://www.facebook.com/ajax/mercury/send_messages.php", form)
+        r = self._post("https://www.facebook.com/ajax/mercury/send_messages.php", data)
         return r.ok
 
     def getThreadList(self, start, end=None):