Index: wp-includes/pluggable.php
===================================================================
--- wp-includes/pluggable.php	(revision 8795)
+++ wp-includes/pluggable.php	(working copy)
@@ -634,11 +634,20 @@
 	do_action('set_auth_cookie', $auth_cookie, $expire, $expiration, $user_id, $scheme);
 	do_action('set_logged_in_cookie', $logged_in_cookie, $expire, $expiration, $user_id, 'logged_in');
 
-	setcookie($auth_cookie_name, $auth_cookie, $expire, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN, $secure);
-	setcookie($auth_cookie_name, $auth_cookie, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure);
-	setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, COOKIEPATH, COOKIE_DOMAIN);
-	if ( COOKIEPATH != SITECOOKIEPATH )
-		setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, SITECOOKIEPATH, COOKIE_DOMAIN);
+	// Set httponly if the php version is >= 5.2.0
+	if ( version_compare(phpversion(), '5.2.0', 'ge') ) {
+		setcookie($auth_cookie_name, $auth_cookie, $expire, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN, $secure, true);
+		setcookie($auth_cookie_name, $auth_cookie, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure, true);
+		setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, COOKIEPATH, COOKIE_DOMAIN, false, true);
+		if ( COOKIEPATH != SITECOOKIEPATH )
+			setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, SITECOOKIEPATH, COOKIE_DOMAIN, false, true);
+	} else {
+		setcookie($auth_cookie_name, $auth_cookie, $expire, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN, $secure);
+		setcookie($auth_cookie_name, $auth_cookie, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure);
+		setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, COOKIEPATH, COOKIE_DOMAIN);
+		if ( COOKIEPATH != SITECOOKIEPATH )
+			setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, SITECOOKIEPATH, COOKIE_DOMAIN);	
+	}
 }
 endif;