I chose 'keep photos on iphone' instead of 'delete' a couple of times in iphoto when syncing my iphone, and now I have hundreds of photos in my iphone that I now want to delete. If I choose 'delete after importing' now, it only deletes the new photos, not the old ones. Deleting photos one by one in the iPhone can take a long time. Is there any way to delete them all at once? thanks!