CKEditor simple image upload functionality
If you ever get to D7, this module does exactly what you're looking for:

One Click Upload module 


  Button for BUEditor and CKEditor which allows upload files in one click.
  
  Features
  
  
  Upload images and insert into editor image code
  Upload files and insert into editor link code
  Multi-upload files and images
  Integration with image styles
  Editable html templates