view_cart.js

function update_cart(val, zip) {
	$.post(update_cart_url,{shipping_method:val,zip:$('#zip_code').val(),ajax:true}, function(data) {
		$('.shipping_cost').html(data);
		update_moip();
	});
}

function update_moip() {
	$('input[name=moip_parcel]').html('');
	var value = parseFloat($('.total-value').text());
	for (var i = 1; i <= 10; i++) {
		installment = (value / i).toFixed(2);
		$('input[name=moip_parcel]').append('<option value="'+i+'">'+i+'x de R$ '+installment+' (Sem Juros)</option>');
	};
}

<?php

Replace...
$content = '<span class="total">'.lang('grand_total').': $R '.format_currency($this->loja->total()).'</span>';
with...
$content = '<span class="total">'.lang('grand_total').': $R <span class="total-value">'.format_currency($this->loja->total(), false).'</span></span>';