diff --git a/scrapy/http/request/form.py b/scrapy/http/request/form.py
index cae56f229..82cb5f5d4 100644
--- a/scrapy/http/request/form.py
+++ b/scrapy/http/request/form.py
@@ -54,7 +54,7 @@ def _urlencode(seq, enc):
     return urlencode(values, doseq=1)
 
 
-def _get_form(response, formname, formnumber, formxpath):
+def _get_form(response, formname, formid, formnumber, formxpath):
     """Find the form element """
     from scrapy.selector.lxmldocument import LxmlDocument
     root = LxmlDocument(response, lxml.html.HTMLParser)