WP 3.0 custom menu in multisite

My blog is a multisite with each section of the site having different colours and header images. The top menu above the header image is created with the WP custom menu.

What I want to achieve is for this menu to be constant across all my subsite so that I don't have to recreate each menu manually each time I update something or add a new subsite.

Apparently it can be done by adding two lines of code immediately before and immediately after the nav bar code in header.php.

I found this in the WordPress forum :

just before the nav bar code put
<?php switch_to_blog(1); ?>
right after the navbar code put
<?php restore_current_blog(); ?>
then it will always show the pages from Blog #1

and it worked for the person who asked the question with the theme they were using.

I am not sure where to place this code in Ata theme files as header.php calls to the functions in the new wp menu file to display the menu.

I have tried inserting this code in several different places to no avail. A couple of those attempts "broke" my blog lol.

Does anyone know how to implement this ? Maybe it's a good one for Flynn to add to the wish list for the next upgrade as more and more users(and clients) are wanting to implement similar features with multisite.