Apache httpd supports PCRE (=perl compatible regular extensions). Be careful of the syntax, because the regex must be enclosed by “/” and you have to use “=~” to enable pcre.
This example redirects “<any>.olddomain.<any>” to “http://www.newdomain.com”
<If "%{HTTP_HOST} =~ /.*olddomain.*/"> Redirect permanent "/" "http://www.newdomain.com/" </If>
This example redirects “<any>.olddomain.<any>” or “www.example.com” to “http://www.newdomain.com”
<If "%{HTTP_HOST} =~ /(.*olddomain.*)|(www.example.com)/"> Redirect permanent "/" "http://www.newdomain.com/" </If>