Jani Hartikainen has posted his technique for making the Doctrine version 1 style "soft delete" in your Doctrine 2 powered application.

Doctrine 1 has the concept of behaviors which you could add to your models. One of these was the soft-delete behavior, which allowed you to "delete" records without really deleting them. Doctrine 2 does not have behaviors due to various reasons. However, I needed a way to have a model which worked like soft-delete. Let's see one approach to creating such behavior in Doctrine 2.

He introduces the idea of a "soft delete" - essentially a flag that gets set to let the rest of the application think that row is essentially deleted. He shows you how to create the similar functionality via a repository that filters the data for you. He includes code to help you along, defining the find/findOneBy/findBy and the example repository that lets you set an "is deleted" property on the object.