Wordpress plugin for allow iframe in the visual Editor

fb_allow_iframe_tinymce.php

<?php
/**
 * Plugin Name: iFrame for TinyMCE
 * Description: Allow iframe in the visual Editor
 * Version:     0.0.1
 * Author:      Frank Bültge
 * Author URI:  http://bueltge.de/
 */

! defined( 'ABSPATH' ) and exit;

add_filter( 'tiny_mce_before_init', 'fb_change_mce_options' );
function fb_change_mce_options( $args ) {

  // Comma separated string od extendes tags
	// Command separated string of extended elements
	$ext = 'iframe[align|longdesc|name|width|height|frameborder|scrolling|marginheight|marginwidth|src]';

	if ( isset( $args['extended_valid_elements'] ) ) {
		$args['extended_valid_elements'] .= ',' . $ext;
	} else {
		$args['extended_valid_elements'] = $ext;
	}
	// maybe; set tiny paramter verify_html
	//$args['verify_html'] = false;

	return $args;
}