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Before installing a "contrib" tool check it's its release notes to confirm that it's Sakai common services dependencies have been updated to bind to the new kernel. Contrib tool information can also be found in Sakai's Confluence wiki.
Adding a 2.6-compatible contrib tool to your build is usually a straightforward process. For example, to add SiteStats to you Sakai build checkout the latest release tag into your sakai-2.6.0 base folder:
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