How to use Zend_Validate twice

I'm using Zend_Validate_Db_NoRecordExists and I would like to validate my Zend_Form against two fields in DB, sample code:

    $phone_1 = new Zend_Form_Element_Text('phone_1');
    $phone_1->addValidator(new Zend_Validate_Db_NoRecordExists(
                            array(
                                'field' => 'phone_1',
                                'table' => 'customer',
                    )))
            ->addValidator(new Zend_Validate_Db_NoRecordExists(
                            array(
                                'field' => 'phone_2',
                                'table' => 'customer',
                    )));

Can I accomplish this?

Create validation chain

$chain = new Zend_Validate();
$foo   = new Zend_Validate_Db_NoRecordExists(...);
$bar   = new Zend_Validate_Db_NoRecordExists(...);
$chain->addValidator($foo)
      ->addValidator($bar);

$element->addValidator($chain); 

UPDATE @Bob Kruithof

Quick and dirty sample using ZF 1.12.3. All code samples and line numbers are from ZF 1.12.3

<?php

$aPaths = array(
    'path/to/zf'
);

set_include_path(implode(PATH_SEPARATOR, $aPaths));

require_once 'Zend/Loader/Autoloader.php';
$autoloader = Zend_Loader_Autoloader::getInstance();

$element = new Zend_Form_Element_Text('testSO');

$chain = new Zend_Validate();
$bar = new Zend_Validate_Regex('/^Test/');
$baz = new Zend_Validate_Regex('/Valid$/');
$chain->addValidator($bar)
      ->addValidator($baz);

$element->addValidator($chain); 

echo PHP_VERSION . ', ' . Zend_Version::getLatest() . PHP_EOL;

var_dump($element->isValid('Test'));
var_dump($element->isValid('Valid'));
var_dump($element->isValid('Test Valid'));

/* output
5.3.8, 1.12.3
bool(false)
bool(false)
bool(true)
*/

?>

Why this works: Zend_Form_Element.php lines 1144 - 1168 sets validators either by Zend_Validate object or by string. You are right - if validators are used with name, not as chain, then as a result one would have single validator. But in result we have:

$this->_validators[$name] = $validator;
/* debugger info:
    $name --> (string) Zend_Validate
    $validator --> Zend_Validate object {
  _validators => array(2) (
    [0] => array(2) (
      [instance] => Zend_Validate_Regex object {
      }
      [breakChainOnFailure] => (bool) false
    )
    [1] => array(2) (
      [instance] => Zend_Validate_Regex object {
      }
      [breakChainOnFailure] => (bool) false
    )
  )
  _messages => array(0)
  _errors => array(0)
  zfBreakChainOnFailure => (bool) false
}
*/

public function addValidator($validator, $breakChainOnFailure = false, $options = array())
    {
        if ($validator instanceof Zend_Validate_Interface) {
            $name = get_class($validator);

            if (!isset($validator->zfBreakChainOnFailure)) {
                $validator->zfBreakChainOnFailure = $breakChainOnFailure;
            }
        } elseif (is_string($validator)) {
            $name      = $validator;
            $validator = array(
                'validator' => $validator,
                'breakChainOnFailure' => $breakChainOnFailure,
                'options'             => $options,
            );
        } else {
            require_once 'Zend/Form/Exception.php';
            throw new Zend_Form_Exception('Invalid validator provided to addValidator; must be string or Zend_Validate_Interface');
        }


        $this->_validators[$name] = $validator;

        return $this;
    }

When we call $element->isValid()) it iterates over all validators inside of the chain - check Zend_Validate.php, lines 91-110:

public function isValid($value)
    {
        $this->_messages = array();
        $this->_errors   = array();
        $result = true;
        foreach ($this->_validators as $element) {
            $validator = $element['instance'];
            if ($validator->isValid($value)) {
                continue;
            }
            $result = false;
            $messages = $validator->getMessages();
            $this->_messages = array_merge($this->_messages, $messages);
            $this->_errors   = array_merge($this->_errors,   array_keys($messages));
            if ($element['breakChainOnFailure']) {
                break;
            }
        }
        return $result;
    }

$this->_validators is our array of validators:

array(2) (
  [0] => array(2) (
    [instance] => Zend_Validate_Regex object {
      _messageTemplates => array(3) (
      )
      _messageVariables => array(1) (
      )
      _pattern => (string) /^Test/
      _value => null
      _messages => array(0)
      _obscureValue => (bool) false
      _errors => array(0)
      _translator => null
      _translatorDisabled => (bool) false
    }
    [breakChainOnFailure] => (bool) false
  )
  [1] => array(2) (
    [instance] => Zend_Validate_Regex object...