I am while using default twenty_ten theme that accompany the most recent Wordpress and modifying it. Among the finest to include a category to particular text inputs inside the new comment form (particularly to include

class="text"
to really make it play nice with Blueprint CSS framework).

I can not locate the area to get this done. Not au fait with PHP but capable of working my way around it generally - cannot appear to discover the shape here.

Any help appreciated.

The comment form is output through the WordPress comment_form() function. To include a CSS class to a particular inputs, you are able to alter the $fields argument when it is known as from the foot of the TwentyTen comments.php file.

Within the example below I have added class="text" towards the author input area:

<?php
    $fields =  array(
        'author' => '<p class="comment-form-author">' . '<label for="author">' . __( 'Name' ) . '</label> ' . ( $req ? '<span class="required">*</span>' : '' ) . '<input class="text" id="author" name="author" type="text" value="' . esc_attr( $commenter['comment_author'] ) . '" size="30"' . $aria_req . ' /></p>',
        'email'  => '<p class="comment-form-email"><label for="email">' . __( 'Email' ) . '</label> ' . ( $req ? '<span class="required">*</span>' : '' ) .           '<input id="email" name="email" type="text" value="' . esc_attr(  $commenter['comment_author_email'] ) . '" size="30"' . $aria_req . ' /></p>',
        'url'   => '<p class="comment-form-url"><label for="url">' . __( 'Website' ) . '</label>' . '<input id="url" name="url" type="text" value="' . esc_attr( $commenter['comment_author_url'] ) . '" size="30" /></p>',
    ); 

    comment_form(array('fields'=>$fields));

?>

Alternatively you can produce a filter inside your theme's functions.php that added the input class for you personally:

function my_comment_fields($fields) {
    foreach($fields as $field){
         // Add the class to your field's input
    }
    return $fields;
}
add_filter('comment_form_default_fields','my_comment_fields');