Adding Menu System

Is there any way to update all the blogs that have use a specific template ?

Eg Created new blog with new blogs template. a few weeks later i have updated a menu system on the base blog, how can i make this change effective on all the blogs that have this template ?

eg
Existing Blog: http://project365.com.au/rosscataldo/

Updated Template with menu under banner: http://project365.com.au/freetemplate/

How can i update previous blogs with new menu automatically ?

Thanks in advance.

Ross