Changes with nginx 0.6.18 27 Nov 2007

*) Change: now the ngx_http_userid_module adds start time microseconds to the cookie field contains a pid value.

*) Change: now the full request line instead of URI only is written to error_log.

*) Feature: variables support in the "proxy_pass" directive.

*) Feature: the "resolver" and "resolver_timeout" directives.

*) Feature: now the directive "add_header last-modified ''" deletes a "Last-Modified" response header line.

*) Bugfix: the "limit_rate" directive did not allow to use full throughput, even if limit value was very high.