+=head2 CGI Options
+
+=over
+
+=item libravatar_uri $gLibravatarUri
+
+URI to a libravatar configuration. If empty or undefined, libravatar
+support will be disabled. Defaults to
+libravatar.cgi, our internal federated libravatar system.
+
+=cut
+
+set_default(\%config,'libravatar_uri','http://'.$config{cgi_domain}.'/libravatar.cgi?email=');
+
+=item libravatar_uri_options $gLibravatarUriOptions
+
+Options to append to the md5_hex of the e-mail. This sets the default
+avatar used when an avatar isn't available. Currently defaults to
+'?d=retro', which causes a bitmap-looking avatar to be displayed for
+unknown e-mails.
+
+Other options which make sense include ?d=404, ?d=wavatar, etc. See
+the API of libravatar for details.
+
+=cut
+
+set_default(\%config,'libravatar_uri_options','');
+
+=item libravatar_default_image
+
+Default image to serve for libravatar if there is no avatar for an
+e-mail address. By default, this is a 1x1 png. [This will also be the
+image served if someone specifies avatar=no.]
+
+Default: $config{web_dir}/1x1.png
+
+=cut
+
+set_default(\%config,'libravatar_default_image',$config{web_dir}.'/1x1.png');
+
+=item libravatar_cache_dir
+
+Directory where cached libravatar images are stored
+
+Default: $config{web_dir}/libravatar/
+
+=cut
+
+set_default(\%config,'libravatar_cache_dir',$config{web_dir}.'/libravatar/');
+
+=item libravatar_blacklist
+
+Array of regular expressions to match against emails, domains, or
+images to only show the default image
+
+Default: empty array
+
+=cut
+
+set_default(\%config,'libravatar_blacklist',[]);
+
+=back