send hostname in dhclient.conf

[Daniel Gonzalez Schiller]

how can i do this that dhclient.conf send my hostname to the dhcp server?
is there any script that copy the entry in /etc/hostname and paste it
on /etc/dhclient.conf?
why itsn't an automatic way like in SuSE (with yast) and in Windows or freebsd?
thank u very much