I have several Sharepoint:PeopleEditor controls on a Web Part which is deployed to a farm. As long as I have the page the control is on checked out the control works fine. I can browse for users and validate the users via the checkNames icon. I even built a javascript function which validates the control when focus is lost. Again everything works perfectly as long as the web part page is checked out.
The catch is that as soon as I publish the page all validation functionality stops working. If I click the CheckNames Icon I get the hourglass icon that just never goes away and nothing is ever validated. If I move away from the CheckNames Icon I get my cursor back and can continue to edit and save the web part form. Users can still browse the directory and select users. The custom javascript validator also fails to work, so they basically have no way of validating any users until they click submit and then the field is validated on a post back.