Modify first site for shared IP. Catch all subdomain in Web Server

One customer with dedicated server has a problem. If a customer create a point in his DNS for subdomain to point to server, and my customer has not create already a correspondent subdomain in server, server show first subdomain create on httpd.conf I've tried several ways on older post in this forum, but any work fine with EA4. Is possible create a subdomain for catch all requests without a properly domain or subdomains that point to shared IP ?