A function to rename keys from an array you provide.

Arr.php

<?php defined('SYSPATH') OR die('No direct script access.');

class Arr extends Kohana_Arr {

	/**
	 * Maps new keys to an array
	 *
	 * Example:
	 *
	 *  $customer_values = Arr::remap_keys($_POST, array(
	 *      'billing_address1' => 'address1', 'billing_address2' => 'address2'
	 *  ));
	 *
	 * @param $values
	 * @param $new_keys
	 *
	 * @return array
	 */
	public static function remap_keys($values, $new_keys) {
		$new_array = array();

		foreach ($values as $key => $value) {
			// if there is a new key to assign
			if (array_key_exists($key, $new_keys)) {
				$new_array[$new_keys[$key]] = $value;
			} else {
				$new_array[$key] = $value;
			}
		}

		return $new_array;

	}

}