Error in some instances

[LSH]

Hi,

I am getting this error in a GAE/Py app

1. ms=2116 cpu_ms=5152 api_cpu_ms=3612 cpm_usd=0.143288 instance=00c61b117c9067bd7cc893963797b9a4bbb358

2. E 2012-01-16 20:24:10.269

   Traceback (most recent call last):

3. E 2012-01-16 20:24:10.269

     File "/base/python_runtime/python_dist/lib/python2.5/wsgiref/handlers.py", line 92, in run

4. E 2012-01-16 20:24:10.269

       self.result = application(self.environ, self.start_response)

5. E 2012-01-16 20:24:10.269

     File "/base/python_runtime/python_lib/versions/1/google/appengine/ext/webapp/_webapp25.py", line 722, in __call__

6. E 2012-01-16 20:24:10.269

       response.wsgi_write(start_response)

7. E 2012-01-16 20:24:10.269

     File "/base/python_runtime/python_lib/versions/1/google/appengine/ext/webapp/_webapp25.py", line 330, in wsgi_write

8. E 2012-01-16 20:24:10.269

       write = start_response('%d %s' % self.__status, self.__wsgi_headers)

9. E 2012-01-16 20:24:10.269

     File "/base/python_runtime/python_dist/lib/python2.5/wsgiref/handlers.py", line 185, in start_response

10. E 2012-01-16 20:24:10.269

        assert type(val) is StringType,"Header values must be strings"

11. E 2012-01-16 20:24:10.269

    AssertionError: Header values must be strings

As you can see, none of my app's code has been launched yet, so it is not related with my coding. Surprisingly, the same request does work sometimes, depending on the instances where it is being launched.