design a primer - how to determind a specific primer in a complete gonome? (Apr/20/2002 )

i've got the complete gonome of a virus and design 10 couples of primers with 'primer premier'.  but i don't know which couple is the most specific to the gonome. could you tell me which free software can help me to determind a specific primer? thanks a lot .
if you know, please send a email to casco0186@sina.com

Can you be more specific. Is your viral genome a part of the mammalian genome or some other library. You may require nested primers if your viral genome is a part of mammalian genome.