the "content management" menu is missing for non-admin users

whenever i log as s non-admin user there is no way to add a page/story/whatever as there is no such item in the admin_menu.

hoever, i can add nodes by going to "www.mysite.com/node/add" - so it seems not to be a problem with permissions.
the same problem appears on 3 different sites.

any clues? thanks!