Index: wp-includes/user.php
===================================================================
--- wp-includes/user.php	(revision 17488)
+++ wp-includes/user.php	(working copy)
@@ -715,29 +715,6 @@
 }
 
 /**
- * Checks if the current user belong to a given blog.
- *
- * @since 3.0.0
- *
- * @param int $blog_id Blog ID
- * @return bool True if the current users belong to $blog_id, false if not.
- */
-function is_blog_user( $blog_id = 0 ) {
-	global $wpdb;
-
-	$current_user = wp_get_current_user();
-	if ( !$blog_id )
-		$blog_id = $wpdb->blogid;
-
-	$cap_key = $wpdb->base_prefix . $blog_id . '_capabilities';
-
-	if ( is_array($current_user->$cap_key) && in_array(1, $current_user->$cap_key) )
-		return true;
-
-	return false;
-}
-
-/**
  * Add meta data field to a user.
  *
  * Post meta data is called "Custom Fields" on the Administration Panels.
Index: wp-includes/deprecated.php
===================================================================
--- wp-includes/deprecated.php	(revision 17488)
+++ wp-includes/deprecated.php	(working copy)
@@ -2602,3 +2602,30 @@
 	return true;
 }
 
+/**
+ * Checks if the current user belong to a given blog. No longer used in core.
+ *
+ * @since MU
+ * @deprecated 3.2
+ *
+ * @param int $blog_id Blog ID
+ * @return bool True if the current user belongs to $blog_id, false if not.
+ */
+function is_blog_user( $blog_id = 0 ) {
+	_deprecated_function( __FUNCTION__, '3.2' );
+	
+	global $wpdb;
+
+	$current_user = wp_get_current_user();
+	
+	if ( !$blog_id )
+		$blog_id = $wpdb->blogid;
+
+	$cap_key = $wpdb->get_blog_prefix( $blog_id ) . 'capabilities';
+	
+	if ( is_array( $current_user->$cap_key ) && in_array( 1, $current_user->$cap_key ) )
+		return true;
+
+	return false;
+}
+