Network theme and search across network sites

Just installed network theme as the opening domain (
Have 3 further sites setup - (WP 3.1 multisite)

When I search within no content is returned.
The other 3 sites all have content, though are using custom post types.

What i get returned is:
Sorry, we can't find the search keyword you're looking for. Please try selecting a menu item from above or to the side of this message to get where you'd like to go.

Can you confirm the search is Network wide...or make any other suggestion.