ZF-10267: Add support for reg-names
Zend_Validate_Hostname should add support for reg-names. See http://tools.ietf.org/html/rfc3986#section-3.2.2 for detials.
This is basically a name composed of most unreserved characters, incl. underscores, tildas etc. You can also use the same type of host names in /etc/hosts for example. It's way more permissive than DNS.
This detection should be off per default