Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 14804)
+++ wp-includes/functions.php	(working copy)
@@ -1311,23 +1311,6 @@
 }
 
 /**
- * Whether today is a new day.
- *
- * @since 0.71
- * @uses $day Today
- * @uses $previousday Previous day
- *
- * @return int 1 when new day, 0 if not a new day.
- */
-function is_new_day() {
-	global $day, $previousday;
-	if ( $day != $previousday )
-		return 1;
-	else
-		return 0;
-}
-
-/**
  * Build URL query based on an associative and, or indexed array.
  *
  * This is a convenient function for easily building url queries. It sets the
Index: wp-includes/deprecated.php
===================================================================
--- wp-includes/deprecated.php	(revision 14804)
+++ wp-includes/deprecated.php	(working copy)
@@ -50,6 +50,25 @@
 }
 
 /**
+ * Whether today is a new day.
+ *
+ * @since 0.71
+ * @deprecated 3.1
+ * @uses $day Today
+ * @uses $previousday Previous day
+ *
+ * @return int 1 when new day, 0 if not a new day.
+ */
+function is_new_day() {
+	_deprecated_function( __FUNCTION__, '3.1' );
+	global $day, $previousday;
+	if ( $day != $previousday )
+		return 1;
+	else
+		return 0;
+}
+
+/**
  * Sets up the WordPress Loop.
  *
  * @since 1.0.1