BuddyPress.org

Try this:

<li<?php if ( is_page( \'about\' ) ) : ?> class=\"selected\"<?php endif; ?>><a href=\"<?php echo $bp->root_domain; ?>/about/\" title=\"<?php _e( \'About\', \'buddypress\' );?>\"><?php _e( \'About\', \'buddypress\' );?></a></li>