Use wordpress standard shortcode API (http://codex.wordpress.org/Shortcode_API)

//  Add Cform [cforms id="2"]
add_shortcode('cforms', 'ds_cformsShortcode');
function ds_cformsShortcode($atts) {
    extract(shortcode_atts(array(
        'id' => '1'
    ), $atts));

    return cforms("","{$id}");
}

It is good for compatibility with other plugins etc. Thank you for your great effort with cforms. Regards Tomas Kapler (http://www.developstudio.com)