auth::artempt does not work on laravel4

$input=[
    'mail' = > Input::get('mail'),
    'password' = > Input::get('password'),
　];

　if(Auth::attempt($input)){
    echo 'Success';
　} else{
    echo 'Failed';
　}

<?php
use Illuminate\Auth\UserInterface;
use Illuminate\Auth\Reminders\RemovableInterface;

class User extensions Eloquent implements UserInterface, RemovableInterface {
    protected$table='users';
    public function getAuthIdentifier(){
        return$this->getKey();
    }
    public function getRememberToken(){
        return$this->remember_token;
    }
    public function getAuthPassword(){
        return $this->password;
    }
    public function setRememberToken($value){
        $this->remember_token=$value;
    }
    public function getRememberTokenName(){
        return 'remember_token';
    }
    public function getReminderEmail(){
        return$this->email;
    }
}