And of course, we should mention that you must verify that the object doesn't contain any other documents. If you delete the object, and that object is referred to by other documents, then you'll render those other documents irretrievable.
Another way to think about it:
If the document was eligible for expiration, you wouldn't need to issue the 'deleteDocs' call -- because it wouldn't be there for you to delete.
You didn't really give us much information about your situation, so I'm wondering if there's a configuration problem you're trying to correct.