Sergey Biryukov

<?php
function my_show_extra_profile_fields( $user ) { ?>

    <h3 style="margin-bottom:20px;">ваш аватар</h3>
    <div id="avatar">
        <img src="<?php if(esc_attr( get_the_author_meta( 'foto', $user->ID ) )!='')
        echo get_bloginfo('home').'/wp-content/uploads/avatars/'.esc_attr(get_the_author_meta('foto', $user->ID ));
        else
        echo get_bloginfo('home').'/wp-content/themes/j2/images/avatar.jpg'; ?>" width="100" alt="Аватар" style="float:left;margin-right:15px;">
        <input type="file" value="" name="foto" id="foto" /><br/>
        <span>Новый аватар должен иметь<br> размер 100x100px и быть не <br> больше 50kb, иначе он не <br>загрузится.</span>
        <br clear="all" />
        <input type="submit" class="avatar-save" value="Обновить аватар" name="submit" />
    </div>

<?php }

add_action( 'personal_options_update', 'my_save_extra_profile_fields' );
add_action( 'edit_user_profile_update', 'my_save_extra_profile_fields' );

function my_add_form_enctype() {
    echo ' enctype="multipart/form-data"';
}
add_action('user_edit_form_tag', 'my_add_form_enctype');

add_action('show_user_profile', 'my_show_extra_profile_fields');
add_action('edit_user_profile', 'my_show_extra_profile_fields');

function my_save_extra_profile_fields( $user_id ) {
    global $my_error_messages;

    if ( !current_user_can( 'edit_user', $user_id ) )
        return false;

    $image = $_FILES['foto']['tmp_name'];
    if ( empty($image) )
        return false;

    $image_info = GetImageSize($image);
    if ( ($_FILES["foto"]["size"] <= 50*1024) and ($image_info[0]<101) and ($image_info[1]<101) )
    {
        move_uploaded_file($image, ABSPATH . get_option('upload_path').'/avatars/'.md5($image));
        update_usermeta($user_id, 'foto', md5($image) );
    } else {
        $my_error_messages = array();
        if ( ($image_info[0]>100) or ($image_info[1]>10) )
            $my_error_messages[] = '<strong>ОШИБКА</strong>: Размер аватара превышает 100x100px!';
        if ( $_FILES["foto"]["size"] > 50*1024 )
            $my_error_messages[] = '<strong>ОШИБКА</strong>: Размер аватара превышает 50kb!';
    }
}

function my_update_errors($errors) {
    global $my_error_messages;

    foreach ( (array) $my_error_messages as $error_message )
        $errors->add( 'avatar', $error_message);

    return $errors;
}
add_action('user_profile_update_errors', 'my_update_errors');
?>