Shoutbox

i am really not too sure that you can change the url of msn spaces, or build a redirect for it.

one thing you CAN do though is in your space just create a blog and put either in it's title or body the link to your company web-page. i know it's not exactly what you were looking for.. but this way when a contact opens your contact card, they will see the link and will be able to click it.