category description and iframe

Hello,

I try to add <iframe> in category description but nothing is displayed.

I have added some code in funcitons.php to prevent wp that strip html :
/**
* Allow HTML in term (category, tag) descriptions
*/
foreach ( array( ‘pre_term_description’ ) as $filter ) {
remove_filter( $filter, ‘wp_filter_kses’ );
if ( ! current_user_can( ‘unfiltered_html’ ) ) {
add_filter( $filter, ‘wp_filter_post_kses’ );
}
}

foreach ( array( ‘term_description’ ) as $filter ) {
remove_filter( $filter, ‘wp_kses_data’ );
}

But it is not worling.
Could you tell me how to show iframe in catagory description ?

Thanks