Can't Access Old Admin Page After Changing Hosts

I moved my domain name to a new host and installed Zencart there. But I still want access to the Admin function on my old account for a number of reasons. My domain name is "mpmedicalsupplies.com".

When I enter the server alias URL ("d243258.u30.websitesource.net/...") to point to the old Admin page, it immediately redirects to mpmedicalsupplies.com on the new host. I have replaced the "mpmedicalsupplies.com" with the server alias in both configure.php files, but it still redirects. Can you tell me what other files point to the domain name?

If it's pervasive, is there any other way I can access my old Admin page?

When using "d243258.u30.websitesource.net" as a URL I see this code:

<SCRIPT LANGUAGE="JavaScript"> <!-- Begin redirTime = "1000"; redirURL = "http://www.mpmedicalsupplies.com/hp_zencart/index.php"; function redirTimer() { self.setTimeout("self.location.href = redirURL;",redirTime); } // End --> </script>

Either you or your Hoster has setup that code within the page.