Problem with Checkbox for Opt in.

I was unable to get the opt-in working as a checkbox. It would always opt the user out, even when the checkbox was checked. Additionally it would throw a warning about not sending an array or object to array_key_exists().

The following code is very crude, but did fix the problem.

function webform2sugar_flatten_form($values){

        include_once(drupal_get_path('module', 'webform2sugar') . "/webform2sugar_fields.inc");

        $descriptions = '';
        $addresses='';
        $opt_in = 0;
        foreach($values as $key => $value){

                if ($key == 'email_opt_in' && !empty($value)) {
                   $data .= '&' . $key.'=yes';
                   $opt_in=1;
                   continue;
                }

                if ($key == 'email_opt_out' && $opt_in) {
                   continue;
                }

                if (!is_array($webform2sugar_available_fields)) {
                   continue;
                }