(dhcpcd is obsolete; It's been removed from Debian because it isThis is the wrong program! DHCPD == "DHCP Daemon", aka, the DHCP server. The program I believe you are talking about is DHClient, or a DHCP Client.
Be very carefull !!!! dhcpd is the DHCP Daemon. dhcpcd is the DHCP Client Daemon.ie. dhcpcd and pump do very similar things, but are both very different to dhcpd.