--- nginx-1.2.3/src/http/ngx_http_upstream.c	2012-09-05 14:39:33.234197951 -0700
+++ nginx-1.2.3-patched/src/http/ngx_http_upstream.c	2012-09-05 14:39:24.504183525 -0700
@@ -2384,6 +2384,7 @@
     c->log->action = "reading upstream";
 
     if (c->read->timedout) {
+        r->headers_out.status = NGX_HTTP_GATEWAY_TIME_OUT;
         ngx_connection_error(c, NGX_ETIMEDOUT, "upstream timed out");
         ngx_http_upstream_finalize_request(r, u, 0);
         return;
@@ -2431,10 +2432,13 @@
 
             if (u->busy_bufs == NULL) {
 
-                if (u->length == 0
-                    || upstream->read->eof
-                    || upstream->read->error)
-                {
+                if (u->length == 0) {
+                    ngx_http_upstream_finalize_request(r, u, 0);
+                    return;
+                }
+
+                if (upstream->read->eof || upstream->read->error) {
+                    r->headers_out.status = NGX_HTTP_BAD_GATEWAY;
                     ngx_http_upstream_finalize_request(r, u, 0);
                     return;
                 }