function majQuantity(qty,i)
{
     quantity = document.cart_quantity['cart_quantity['+i+']'].value;
     quantity = parseInt(quantity) + parseInt(qty)
     if (quantity < 1)
     {
      quantity = 1;
     }
     document.cart_quantity['cart_quantity['+i+']'].value = quantity;
}

 function mjQuantity(qty,id)
    {
     var formProduct = 'cart_quantity_'+id;
     var inputObj = document.forms[formProduct].quantity;

     quantity = inputObj.value;
     quantity = parseInt(quantity) + parseInt(qty)
     if (quantity < 1)
     {
      quantity = 1;
     }
     inputObj.value = quantity;
    }


function update_qnt(arg) {
var oldvalue = eval(document.cart_quantity.quantity.value);
var next = 0;

if(oldvalue == 1 && arg == -1) {
document.cart_quantity.quantity.value = 1;
next = 1;
}
if(oldvalue == 99 && arg == 1) {
document.cart_quantity.quantity.value = 99;
next = 1;
}

if(next == 0) {
document.cart_quantity.quantity.value = oldvalue + arg;
} 
}