First open your head
Change the logo url with this:
<img src="'.$config['homeurl'].'/images/logo/'.$config['logourl'].'">Open dir images create one dir with name "logo"
Donwload my file so you can see 2 file.. logo.php and sql
Import sql to your db
Import logo.php to admin/includes
Open your index.php on admin/ add my code to access logo.php
So you can up more logo and select anywhere without login to root..
Thanks