I'm trying to test the workflow functionality in Alfresco 4.2 Community, so I created some user accounts and sites. I logged in to a few of them and created some sites and content. For now I just wanted something simple to test workflows, I upload a document and send it to an user for review. When I try to use one of the default workflows that seems to fit that scenario I can't find my users in the select users dialog. I can find some the already existing users (Alice Beecher, Guest, Admin, Mike Jackson).
I also tried searching for them through the People search, but they are not visible there either. I've logged in and joined a test site with some of the users, and have tried to create the workflow from inside and outside the test site. Is there something that I have to enable on the users for them to be visible on searches and when creating workflows?