TemplateNotFound: system/error.html

Hi,
I followed the instructions, opened an appengine app, and now I get this error:
TemplateNotFound: system/error.html
Traceback:
controller.py:37 in render
controller.py:53 in render_view
controller.py:110 in error
drydrop_handler.py:325 in route
drydrop_handler.py:283 in get

You can check it out here:
http://freeappincubator.appspot.com/

I also got some warnings during
upload of drydrop using appcfg.py --email=Yoav.Zibin@gmail.com update .
I got these warnings:
C:\Program Files (x86)\Google\google_appengine\google\appengine\api\search\searc
h.py:232: UserWarning: DocumentOperationResult._code is deprecated. Use Operatio
nResult._code instead.
'Use OperationResult.%s instead.' % (name, name))
C:\Program Files (x86)\Google\google_appengine\google\appengine\api\search\searc
h.py:232: UserWarning: DocumentOperationResult._CODES is deprecated. Use Operati
onResult._CODES instead.
'Use OperationResult.%s instead.' % (name, name))
Application: freeappincubator; version: 1
Host: appengine.google.com