note 29933 rejected from function.unlink by betz

If you have write permission to the directory, you can unlink files, but you can't unlink non-empty directories you can't write to. does anybody know a way round this, perhaps using chown or like to change the directory owner first. I've tried everything, and i can do it if i logon interactively, but i want some way of being able to do it in php. something equivalent to chown user_id some_dir rm -r some_dir without using system or exec.