question, are you wanting to eventually put them back on your iphone? and still be able to delete them?
if so then ssh into you phone, under the media/dcim/apple100 copy both your misc folder and all of your pictures... the misc folder contain important thumbnail photos the the photos app uses to preview the actual photo.
when you need to put them back on your phone just past them back in your apple100 folder and all should be well
might have to check the folder permissions to make sure they have not changed.