gentoo-overlay/net-mail/vqadmin/files/postinstall-en.txt

You need to setup authentication. For apache do the following:

<Files ${VHOST_CGIBINDIR}/${PN}>
	AuthType Basic
	AuthUserFile ${VHOST_CONFDIR}${PN}.passwd
	AuthName ${PN}
	Require valid-user
</Files>

The create the password file like this:

htpasswd -c ${VHOST_CONFDIR}${PN}.passwd <user>