diff --git a/wp-admin/includes/deprecated.php b/wp-admin/includes/deprecated.php
index 343e44132d..38da949b62 100644
--- a/wp-admin/includes/deprecated.php
+++ b/wp-admin/includes/deprecated.php
@@ -288,6 +288,346 @@ function get_nonauthor_user_ids() {
 	return $wpdb->get_col( $wpdb->prepare("SELECT user_id FROM $wpdb->usermeta WHERE meta_key = %s AND meta_value = '0'", $level_key) );
 }
 
+if ( !class_exists('WP_User_Search') ) :
+/**
+ * WordPress User Search class.
+ *
+ * @since 2.1
+ * @deprecated 3.1.0
+ */
+class WP_User_Search {
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var unknown_type
+	 */
+	var $results;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var unknown_type
+	 */
+	var $search_term;
+
+	/**
+	 * Page number.
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var int
+	 */
+	var $page;
+
+	/**
+	 * Role name that users have.
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var string
+	 */
+	var $role;
+
+	/**
+	 * Raw page number.
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var int|bool
+	 */
+	var $raw_page;
+
+	/**
+	 * Amount of users to display per page.
+	 *
+	 * @since unknown
+	 * @access public
+	 * @var int
+	 */
+	var $users_per_page = 50;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var unknown_type
+	 */
+	var $first_user;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var int
+	 */
+	var $last_user;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var string
+	 */
+	var $query_limit;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since 3.0.0
+	 * @access private
+	 * @var string
+	 */
+	var $query_orderby;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since 3.0.0
+	 * @access private
+	 * @var string
+	 */
+	var $query_from;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since 3.0.0
+	 * @access private
+	 * @var string
+	 */
+	var $query_where;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var int
+	 */
+	var $total_users_for_query = 0;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var bool
+	 */
+	var $too_many_total_users = false;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var unknown_type
+	 */
+	var $search_errors;
+
+	/**
+	 * {@internal Missing Description}}
+	 *
+	 * @since unknown
+	 * @access private
+	 * @var unknown_type
+	 */
+	var $paging_text;
+
+	/**
+	 * PHP4 Constructor - Sets up the object properties.
+	 *
+	 * @since unknown
+	 *
+	 * @param string $search_term Search terms string.
+	 * @param int $page Optional. Page ID.
+	 * @param string $role Role name.
+	 * @return WP_User_Search
+	 */
+	function WP_User_Search ($search_term = '', $page = '', $role = '') {
+		_deprecated_function( __FUNCTION__, '3.1', 'WP_User_Query' );
+
+		$this->search_term = $search_term;
+		$this->raw_page = ( '' == $page ) ? false : (int) $page;
+		$this->page = (int) ( '' == $page ) ? 1 : $page;
+		$this->role = $role;
+
+		$this->prepare_query();
+		$this->query();
+		$this->prepare_vars_for_template_usage();
+		$this->do_paging();
+	}
+
+	/**
+	 * {@internal Missing Short Description}}
+	 *
+	 * {@internal Missing Long Description}}
+	 *
+	 * @since unknown
+	 * @access public
+	 */
+	function prepare_query() {
+		global $wpdb;
+		$this->first_user = ($this->page - 1) * $this->users_per_page;
+
+		$this->query_limit = $wpdb->prepare(" LIMIT %d, %d", $this->first_user, $this->users_per_page);
+		$this->query_orderby = ' ORDER BY user_login';
+
+		$search_sql = '';
+		if ( $this->search_term ) {
+			$searches = array();
+			$search_sql = 'AND (';
+			foreach ( array('user_login', 'user_nicename', 'user_email', 'user_url', 'display_name') as $col )
+				$searches[] = $col . " LIKE '%$this->search_term%'";
+			$search_sql .= implode(' OR ', $searches);
+			$search_sql .= ')';
+		}
+
+		$this->query_from = " FROM $wpdb->users";
+		$this->query_where = " WHERE 1=1 $search_sql";
+
+		if ( $this->role ) {
+			$this->query_from .= " INNER JOIN $wpdb->usermeta ON $wpdb->users.ID = $wpdb->usermeta.user_id";
+			$this->query_where .= $wpdb->prepare(" AND $wpdb->usermeta.meta_key = '{$wpdb->prefix}capabilities' AND $wpdb->usermeta.meta_value LIKE %s", '%' . $this->role . '%');
+		} elseif ( is_multisite() ) {
+			$level_key = $wpdb->prefix . 'capabilities'; // wpmu site admins don't have user_levels
+			$this->query_from .= ", $wpdb->usermeta";
+			$this->query_where .= " AND $wpdb->users.ID = $wpdb->usermeta.user_id AND meta_key = '{$level_key}'";
+		}
+
+		do_action_ref_array( 'pre_user_search', array( &$this ) );
+	}
+
+	/**
+	 * {@internal Missing Short Description}}
+	 *
+	 * {@internal Missing Long Description}}
+	 *
+	 * @since unknown
+	 * @access public
+	 */
+	function query() {
+		global $wpdb;
+
+		$this->results = $wpdb->get_col("SELECT DISTINCT($wpdb->users.ID)" . $this->query_from . $this->query_where . $this->query_orderby . $this->query_limit);
+
+		if ( $this->results )
+			$this->total_users_for_query = $wpdb->get_var("SELECT COUNT(DISTINCT($wpdb->users.ID))" . $this->query_from . $this->query_where); // no limit
+		else
+			$this->search_errors = new WP_Error('no_matching_users_found', __('No matching users were found!'));
+	}
+
+	/**
+	 * {@internal Missing Short Description}}
+	 *
+	 * {@internal Missing Long Description}}
+	 *
+	 * @since unknown
+	 * @access public
+	 */
+	function prepare_vars_for_template_usage() {
+		$this->search_term = stripslashes($this->search_term); // done with DB, from now on we want slashes gone
+	}
+
+	/**
+	 * {@internal Missing Short Description}}
+	 *
+	 * {@internal Missing Long Description}}
+	 *
+	 * @since unknown
+	 * @access public
+	 */
+	function do_paging() {
+		if ( $this->total_users_for_query > $this->users_per_page ) { // have to page the results
+			$args = array();
+			if( ! empty($this->search_term) )
+				$args['usersearch'] = urlencode($this->search_term);
+			if( ! empty($this->role) )
+				$args['role'] = urlencode($this->role);
+
+			$this->paging_text = paginate_links( array(
+				'total' => ceil($this->total_users_for_query / $this->users_per_page),
+				'current' => $this->page,
+				'base' => 'users.php?%_%',
+				'format' => 'userspage=%#%',
+				'add_args' => $args
+			) );
+			if ( $this->paging_text ) {
+				$this->paging_text = sprintf( '<span class="displaying-num">' . __( 'Displaying %s&#8211;%s of %s' ) . '</span>%s',
+					number_format_i18n( ( $this->page - 1 ) * $this->users_per_page + 1 ),
+					number_format_i18n( min( $this->page * $this->users_per_page, $this->total_users_for_query ) ),
+					number_format_i18n( $this->total_users_for_query ),
+					$this->paging_text
+				);
+			}
+		}
+	}
+
+	/**
+	 * {@internal Missing Short Description}}
+	 *
+	 * {@internal Missing Long Description}}
+	 *
+	 * @since unknown
+	 * @access public
+	 *
+	 * @return unknown
+	 */
+	function get_results() {
+		return (array) $this->results;
+	}
+
+	/**
+	 * Displaying paging text.
+	 *
+	 * @see do_paging() Builds paging text.
+	 *
+	 * @since unknown
+	 * @access public
+	 */
+	function page_links() {
+		echo $this->paging_text;
+	}
+
+	/**
+	 * Whether paging is enabled.
+	 *
+	 * @see do_paging() Builds paging text.
+	 *
+	 * @since unknown
+	 * @access public
+	 *
+	 * @return bool
+	 */
+	function results_are_paged() {
+		if ( $this->paging_text )
+			return true;
+		return false;
+	}
+
+	/**
+	 * Whether there are search terms.
+	 *
+	 * @since unknown
+	 * @access public
+	 *
+	 * @return bool
+	 */
+	function is_search() {
+		if ( $this->search_term )
+			return true;
+		return false;
+	}
+}
+endif;
+
 /**
  * Retrieve editable posts from other users.
  *