How to use piwik in a dokuwiki farm?

hello all,
i’ve just installed the latest version. It works well. But the site contains many users webpages, written in dokuwiki.
The piwik plugin for dokuwiki seems to be about one installation.
I prefer not to add javascript code to every page created with dokuwiki, i guess there is an ability to do it on a single location? Am i wrong?

anybody can help?

thanks in advance,

gerard