nested error_page

[Mauro Stettler]

hi

i have a situtation where i would need something similar to this:

location / {
  error_page 404 = /fallback_all;
  // do a request to get content from memcache, if not found go to /fallback_all
}

location = /fallback_all {
  internal;
  error_page 404 = @404;
  // do a request to get content from fastcgi, if not found go to @404
}

location @404 {
  internal;
  // real 404 page
}

but this doesn't work. if the fastcgi returns a 404 then nginx will
just display its own error page and ignore the second error_page
directive. i'm guessing that the reason is that at the first 404 error
it already sets the ngx_http_request_t->err_status to something which
makes it ignore the second 404.

is there any way around this? i could probably make the fastcgi return
some other code, but i'm also not sure if this will make it work then.
is there any directive which could make the second error_page work?
something to allow nested error_pages

thanks,

mauro