wilderness - 12:11 am on Dec 14, 2012 (gmt 0)
I'm still frightened of using htaccess in the httpd.conf file.
The procedures within a httpd.conf file are different than for a standard htaccess file.
Others will need to advise you of those differences, as I know nothing of httpd.conf.
A solution is to use the SetEnvIfNoCase Referer (mod_setenvif; Apache)
In the log example you provided I see four potential words:
You'll also need to set an environment variable (env=), then add that variable word you select onto the end of SetEnvIfNoCase Referer line.
FWIW, if you site has a vulnerability to allow access around your configuration via baidu refrerals, than the same vulnerability exists for other search engines as well.
Thus you need to determine a solution that works effectively.