Just for your info if you are looking to multisite with themes for the different sites be sure to update all the links on the images for the themes. As stupid as it seems this one had me going for a litle while. They did mention in the doc.s about putting in the extra link for the logo.gif but not about the themes. So where your theme use to have a link like.
img src="themes/$thename/images/topleft.gif" border=0 width=622 height=109 alt=""
You should replace all image tages like this
img src="".WHERE_IS_PERSO."themes/$thename/images/topleft.gif" border=0 width=622 height=109 alt=""
There is also one minor adjustment to the whoisinc.php which made life a little easierYou have to add a . to the www servername ie.
$serverName = str_replace("www.","",$serverName);
So if your looking for help just contact me