meta description problem with theme "Nest"

hi all,

I have problem with my theme Nest , the meta description is missing, while its working with default theme “Twenty Eleven”.

I followed the following instruction in FAQ.
http://semperfiwebdesign.com/blog/all-in-one-seo-pack/all-in-one-seo-faq/

the wp_head(); is already available in theme “Nest”.

http://wordpress.org/extend/plugins/all-in-one-seo-pack/