diff --git a/tailbone/forms/core.py b/tailbone/forms/core.py
index 9624f6fb..496d59ee 100644
--- a/tailbone/forms/core.py
+++ b/tailbone/forms/core.py
@@ -1156,7 +1156,7 @@ class Form(object):
         value = self.obtain_value(record, field_name)
         if value is None:
             return ""
-        app = self.get_rattail_app()
+        app = self.request.rattail_config.get_app()
         value = app.localtime(value)
         return raw_datetime(self.request.rattail_config, value)
 
@@ -1186,7 +1186,7 @@ class Form(object):
         value = self.obtain_value(obj, field)
         if value is None:
             return ""
-        app = self.get_rattail_app()
+        app = self.request.rattail_config.get_app()
         return app.render_quantity(value)
 
     def render_percent(self, obj, field):