--- template.php
+++ (clipboard)
@@ -111,36 +111,42 @@
   
   // Build array of helpful body classes
   $body_classes = array();
+	// for sub themes
+	$sub_body_classes = $vars['sub_body_classes_array'];
   // Page user is logged in
-  $body_classes[] = ($vars['logged_in']) ? 'logged-in' : 'not-logged-in';
+  $body_classes['is_logged_in'] = ($vars['logged_in']) ? 'logged-in' : 'not-logged-in';
   // Page is front page
-  $body_classes[] = ($vars['is_front']) ? 'front' : 'not-front'; 
+  $body_classes['is_front'] = ($vars['is_front']) ? 'front' : 'not-front'; 
   
   //Clean these strings from special characters (TODO: do we need this check?)
   $_page_type = str_replace(array('][', '_', ' '), '-', arg(0));
   $_node_type = str_replace(array('][', '_', ' '), '-', $vars['node']->type);
   // Page type (for admin, node, etc.)
-  $body_classes[] = preg_replace('![^abcdefghijklmnopqrstuvwxyz0-9-_]+!s', '', 'page-' . $_page_type);
+  $body_classes['page_type'] = preg_replace('![^abcdefghijklmnopqrstuvwxyz0-9-_]+!s', '', 'page-' . $_page_type);
   //If node page, print node type
   if (isset($vars['node']) && $vars['node']->type) {
-    $body_classes[] = 'node-type-'. $_node_type;
+    $body_classes['node_type'] = 'node-type-'. $_node_type;
   }
   
   //Add classes depended on sidebars
   if ($vars['left'] && $vars['right']) {
-    $body_classes[] = 'two-sidebars';
+    $body_classes['sidebars'] = 'two-sidebars';
   } elseif (!$vars['left'] && !$vars['right']){
-    $body_classes[] = 'no-sidebars';
+    $body_classes['sidebars'] = 'no-sidebars';
   } else{
-    $body_classes[] = 'one-sidebar';
+    $body_classes['sidebars'] = 'one-sidebar';
   }
 
   if ($vars['left']) {
-    $body_classes[] = 'with-sidebar-first';
+    $body_classes['is_sidebar_first'] = 'with-sidebar-first';
   }
   if ($vars['right']) {
-    $body_classes[] = 'with-sidebar-second';
+    $body_classes['is_sidebar_second'] = 'with-sidebar-second';
   }
+	//merge with sub body classes
+	if (is_array($sub_body_classes)) {
+		$body_classes = array_merge($body_classes, $sub_body_classes);
+	}
   $body_classes = array_filter($body_classes); // Remove empty elements
   $vars['body_classes'] = implode(' ', $body_classes);// Create class list separated by spaces
 }