ref-sdr-sdram-vhdl controller reference design missing components

Hi all, I am new to VHDL design and I'm trying to the SDRAM controller code found here http://www.altera.com/products/ip/altera/ocore_sdr_sdram.html.

It appears to be incomplete though. When I try to simulate I get two unbound warnings to missing components "altclklock" and "mt481c8m16a2". Consequently the code does not produce any results.

Does anyone know if these components are available anywhere?

Thanks