I need to use 2 listboxes in the same page, I fix here one error

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@4300 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Form/ListBox.py

@@ -909,6 +909,8 @@ class ListBoxWidget(Widget.Widget):
             start = int(start)
           except (TypeError, KeyError):
             start = params.get('list_start',0)
+            if type(start) is type([]):
+              start = start[0]
             start = int(start)
           start = max(start, 0)