Have a look at:
http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/implementing_an_approval_mechanism
http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/modifying_the_entry_page
http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/creating_a_workflow
http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/connecting_the_workflow_to_a_trigger_function
http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/approving_entries http://ez.no/products/ez_publish_cms/documentation/building_an_ez_publish_site/the_guestbook/the_runcronjob_script
in order for a setp by step guide. It's for 3.4 but not a lot has changed since then with these features.
