RewriteEngine on

RewriteBase "/log4net/"

RewriteCond %{REQUEST_URI} !^/log4net/log4net-1.*$
RewriteRule ^(.*)/release/sdk/html/AllMembers_(.*)$ $1/release/sdk/html/$2

RewriteCond %{REQUEST_URI} !^/log4net/log4net-\d.\d.*$
RewriteRule ^(.*)$ log4net-2.0.9/$1