Sharepoint Feature Visibility

In Sharepoint 2007 I h开发者_如何学Pythonave installed some commerial components. They all appear in the "Central Administration > Application Management > Manage Web Application Features Visibility" page in the administration site. All features in the list as shown as "Shown" (not hidden).

When I switch to the "Team Site > Site Settings > Site Features" management page in the main site, only 2 of them appear. Both I have "Activated"

This is a new SP install on a new WIndows 2008 Standard Server VM.

Any pointers to find out why the Features don't all appear in "Site Features" activation screen?

The feature definition has two interesting attributes: Scope and Hidden.

Scope can be Web, Site, WebApplication or Farm. It explains why a given feature is visible in the site settings page for a site, a site collection or in central admin (it also determines what elements can be in the feature, but this is off-topic).

Hidden can be True or False. Only when the value is True is the feature visible in any admin screen.