I am trying to get a multisite network up and running.

Hi. I am trying to get a multisite network up and running. I have the basics of the multisite OK, but domain mapping is causing me trouble.
I have a dedicated IP address for the domain http://www.muremedia.com, which is the primary site of the network.
I have tried both path and subdomain configs,but I am not having any luck, and now cannot get to the individual sites, that is, all sites go the to the primary site.
e.g. hazen.muremedia.com hazenreed.com
both end up going to http://www.muremedia.com

Any help would be appreciated.