delete entries doesn't delete uploaded files/images

I added an upload file option and when I delete an entry the URL to the uploaded file (an image in this case) still works (meaning the file wasn't deleted with the entry). There doesn't seem to be any way to delete that file short of FTP. I can see how this could be exploited by spammers uploading porn to my blog and then when I delete the bogus entries the porn stays behind and they can embed links to it in their sites using my bandwidth. Not sure if there is an easy way to have the delete entry function also delete the associated image/file or not.

As long as you have the ability to delete files from your host:

$tmpfile = "/tmp/someimage.jpg";
unlink($tmpfile);

You would add this in a hook while the form is being processed, but before it is updated.