PDC & ADC Trust Relationship

Hi,

I have created One Win 2K3 Ent Server as a Primary DC Second Win 2k3 Ent Server as a Additional DC.

Now i wish that when my Primary Dc get crash in that time my Additional Dc should work as a PDC. Can any one help me out…, i don’t know the steps… Plz help..

Currently if i crash my PDC (shutdown), my additional Dc does not work as a PDC…