Delete temporary resized files during new file upload

Here is how flash uploader works in In-Portal:
1. image is uploaded in /system/tmp/ folder
2. images, older then 1 day are deleted from /system/tmp/ folder (if user uploaded image, but never submitted a form)
3. image thumbnail is generated in /system/tmp/resized/ folder
4. image is moved from /system/tmp to /system/images/final_location_folder

There is clearly 1 item missing where images older then 1 day are deleted from /system/tmp/resized/ folder as well.