custom url for zoho mail/portal

custom url for zoho mail/portal

I'm noticing that despite this page stating, " Adding a new CNAME (mail.yourdomain.com) and pointing it to business.zoho.com will display the domain URL across all the pages," that my domain does not display on all pages, in fact once logged in, it shows "https://mail.zoho.com/biz/index.do?Requested_Domain=mail.yourdomain.com" (where "yourdomain.com" is my actual domain) instead of "mail.mydomain.com/biz/index.do." Is this normal? Thanks very much.