nginx 0.2.0 *) The pid-file names used during online upgrade was changed and now is not required a manual rename operation. The old master process adds the ".oldbin" suffix to its pid-file and executes a new binary file. The new master process creates usual pid-file without the ".newbin" suffix. If the master process exits, then old master process renames back its pid-file with the ".oldbin" suffix to the pid-file without suffix. *) Change: the "worker_connections" directive, new name of the "connections" directive; now the directive specifies maximum number of connections, but not maximum socket descriptor number. *) Feature: SSL supports the session cache inside one worker process. *) Feature: the "satisfy_any" directive. *) Change: the ngx_http_access_module and ngx_http_auth_basic_module do not run for subrequests. *) Feature: the "worker_rlimit_nofile" and "worker_rlimit_sigpending" directives. *) Bugfix: if all backend using in load-balancing failed after one error, then nginx did not try do connect to them during 60 seconds. *) Bugfix: in IMAP/POP3 command argument parsing. Thanks to Rob Mueller. *) Bugfix: errors while using SSL in IMAP/POP3 proxy. *) Bugfix: errors while using SSI and gzipping. *) Bugfix: the "Expires" and "Cache-Control" header lines were omitted from the 304 responses. Thanks to Alexandr Kukushkin.

--- a/src/http/modules/ngx_http_headers_filter_module.c
+++ b/src/http/modules/ngx_http_headers_filter_module.c
@@ -82,7 +82,10 @@ ngx_http_headers_filter(ngx_http_request
     ngx_table_elt_t          *expires, *cc, **ccp;
     ngx_http_headers_conf_t  *conf;
 
-    if (r->headers_out.status != NGX_HTTP_OK || r->main) {
+    if ((r->headers_out.status != NGX_HTTP_OK
+         && r->headers_out.status != NGX_HTTP_NOT_MODIFIED)
+        || r->main)
+    {
         return ngx_http_next_header_filter(r);
     }