Changes with nginx 1.2.8 02 Apr 2013
*) Bugfix: new sessions were not always stored if the "ssl_session_cache shared" directive was used and there was no free space in shared memory. Thanks to Piotr Sikora.
*) Bugfix: responses might hang if subrequests were used and a DNS error happened during subrequest processing. Thanks to Lanshun Zhou.
*) Bugfix: in the ngx_http_mp4_module. Thanks to Gernot Vormayr.
*) Bugfix: in backend usage accounting.