OOPS on /builders page

When I am logged in as one of offspring admins, I get an OOPS on offspring.linaro.org/builders

Traceback (most recent call last):
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/core/handlers/base.py", line 100, in get_response
    response = callback(request, *callback_args, **callback_kwargs)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/contrib/auth/decorators.py", line 25, in _wrapped_view
    return view_func(request, *args, **kwargs)
  File "/srv/offspring.linaro.org/lib/offspring/web/queuemanager/views.py", line 102, in builders
    context_instance=RequestContext(request))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/shortcuts/__init__.py", line 20, in render_to_response
    return HttpResponse(loader.render_to_string(*args, **kwargs), **httpresponse_kwargs)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/loader.py", line 186, in render_to_string
    return t.render(context_instance)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 173, in render
    return self._render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 167, in _render
    return self.nodelist.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 796, in render
    bits.append(self.render_node(node, context))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 809, in render_node
    return node.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/loader_tags.py", line 125, in render
    return compiled_parent._render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 167, in _render
    return self.nodelist.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 796, in render
    bits.append(self.render_node(node, context))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 809, in render_node
    return node.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/loader_tags.py", line 62, in render
    result = block.nodelist.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 796, in render
    bits.append(self.render_node(node, context))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 809, in render_node
    return node.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/defaulttags.py", line 174, in render
    nodelist.append(node.render(context))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/defaulttags.py", line 232, in render
    return self.nodelist_true.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 796, in render
    bits.append(self.render_node(node, context))
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 809, in render_node
    return node.render(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 844, in render
    output = self.filter_expression.resolve(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 553, in resolve
    obj = self.var.resolve(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 696, in resolve
    value = self._resolve_lookup(context)
  File "/srv/offspring.linaro.org/.virtualenv/lib/python2.6/site-packages/django/template/__init__.py", line 725, in _resolve_lookup
    current = getattr(current, bit)
  File "/srv/offspring.linaro.org/lib/offspring/web/queuemanager/models.py", line 409, in estimated_completion
    if int(hours) < 1:
ValueError: invalid literal for int() with base 10: '27 days, 23'