I often regocnize that urls of wordpress blogs have a session-id at the end. As we know, this is not very good for ranking in search engines. For Google such sites are duplicate content, because they have a different url, but the same content. The result is, that those sites will we ranked lower as before.
If you use wordpress for searchengine-optimization (seo), it is very bad to get penelized by Google because of these duplicate sites. The prevent this, I wrote a little plugin, which checks the url of an article. If the script recognizes a session-id (PHPSESSID) at the end of the url, it sends a status "HTTP/1.1 301 Moved Permanently" and redirects the user (and Google) to the correct permalink of the post.
If you have the possibility to change the php.ini of your host, please insert or change the following lines:
php_value session.use_trans_sid 0
php_value session.use_only_cookies 1
The changes in the php.ini tell your webserver, that he should not send session-variables within the url. Instead he always has to send them via cookies.
The installation is very easy: Just download the file, unzip it, put it in the wp-content/plugins/ folder and activate it under "Plugins". It has no config-menue… it just works.
Dontation? No thanks!
If you like my plugins, please put my website on your blogroll. This will make me happy!