register_user.tpl

<div class="register_form" id="register_form_wrap">
    <div class="row">
        <div class="span9">
            {$register_form}
        </div>
    </div>
    <a href="{$estate_folder}/pubic_license.html" id="regrule">Правила пользования сайтом</a>
</div>
{literal}
<script>
$(document).ready(function(){
    var iam_agree=$('#register_form_wrap input[name=iam_agree]');
    var form=$('#register_form_wrap form');

    $('#register_form_wrap div[alt=iam_agree] .controls').prepend($('a#regrule'));


    if(iam_agree.is(':checked')){
        form.find('#formsubmit').prop('disabled', false);
    }else{
        form.find('#formsubmit').prop('disabled', true);
    }

    iam_agree.change(function(){
        if(iam_agree.is(':checked')){
            form.find('#formsubmit').prop('disabled', false);
        }else{
            form.find('#formsubmit').prop('disabled', true);
        }
    });

    form.submit(function(){
        if(iam_agree.is(':checked')){
            return true;
        }else{
            return false;
        }
    });
});
</script>
{/literal}