Comment 1 for bug 1050852

To reproduce, grab lp:python-oops-tools
make
bin/buildout
bin/django syncdb
edit bin/oopstools.wsgi and make the end be
application = make_app(application, config, oops_on_status=['500'],
    soft_start_timeout=500)
from wsgiref.simple_server import make_server
make_server('127.0.0.1', 8080, application).serve_forever()

Apply this patch:
=== modified file 'src/oopstools/oops/models.py'
--- src/oopstools/oops/models.py 2012-07-27 04:27:53 +0000
+++ src/oopstools/oops/models.py 2012-09-14 10:45:28 +0000
@@ -554,6 +554,7 @@

     @readproperty
     def parsed_oops(self):
+ import time;time.sleep(1)
         self.parsed_oops = _get_oops(self.pathname)
         return self.parsed_oops

And finally run
bin/py bin.oopstools.wsgi
and hit any existing oops. If you don't have one, delete the 404.html template and hit a missing page. That will generate an oops (and you'll need amp2disk running to nab it and load it), then you can visit the oops, the sleep will kick in and the race or whatever it is will show up.