BuddyPress.org

As @LPH2005 mentioned above, create a child theme if you haven’t had already. Note that you must be using WP 3.0 to make the following work:

1. open up functions.php file and add
add_theme_support( ‘menus’ );

2. open up header.php, and add
http://wordpress.pastebin.com/XbrWdhWp
replacing BP navigation items (if you’re on BP 1.3 trunk where BP components are rendered as Pages) or after the BP navigation items (pre BP 1.3 where there is still distinction between regular Pages and BP components)