STYLESHEETPATH not defined in theme.php

I see where it is defined in default-contants.php but it is not set properly in the function, (line 1075)

function locate_template($template_names, $load = false, $require_once = true ) {
	$located = '';
	foreach ( (array) $template_names as $template_name ) {
		if ( !$template_name )
			continue;

		if ( file_exists(STYLESHEET . '/' . $template_name)) {
			$located = STYLESHEET . '/' . $template_name;
			break;
		} else if ( file_exists(TEMPLATEPATH . '/' . $template_name) ) {
			$located = TEMPLATEPATH . '/' . $template_name;
			break;
		}
	}

but if I substitute get_stylesheet_directory() for STYLESHEET, then all is well.

Is this a bug or did I mess something up?
Using buddypress 1.2.9 and wordpress 3.2