mapping the first part of a domainname to a default domainname

Hi there, I think it's off topic, but anyway... In the dns records of a domain you can insert multiple hostnames that are part of the domain. For example: www1.domain.com, www2.domain.com. Is there a way you can put in wildcards for the hostname so that if the specified host is not found in the dns of the domain it redirects the visitor to a specified default domain. For example if the visitor types in johndoe.domain.com he gets redirected to www.domain.com Thanks, Olav