The Problem with Schema

<?xml version="1.0" encoding="ISO-8859-1"?>

<shiporder orderid="889923"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="shiporder.xsd">
  <orderperson>John Smith</orderperson>
  <shipto>
    <name>Ola Nordmann</name>
    <address>Langgt 23</address>
    <city>4000 Stavanger</city>
    <country>Norway</country>
  </shipto>
  <item>
    <title>Kittens For Beginners</title>
    <note>Special Edition</note>
    <quantity>1</quantity>
    <price>10.90</price>
  </item>
  <item>
    <title>Dogs For Beginners</title>
    <quantity>1</quantity>
    <price>9.90</price>
  </item>
</shiporder>

<?xml version="1.0" encoding="ISO-8859-1" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:element name="shiporder">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="orderperson" type="xs:string"/>
      <xs:element name="shipto">
        <xs:complexType>
          <xs:sequence>
            <xs:element name="name" type="xs:string"/>
            <xs:element name="address" type="xs:string"/>
            <xs:element name="city" type="xs:string"/>
            <xs:element name="country" type="xs:string"/>
          </xs:sequence>
        </xs:complexType>
      </xs:element>
      <xs:element name="item" maxOccurs="unbounded">
        <xs:complexType>
          <xs:sequence>
            <xs:element name="title" type="xs:string"/>
            <xs:element name="note" type="xs:string" minOccurs="0"/>
            <xs:element name="quantity" type="xs:positiveInteger"/>
            <xs:element name="price" type="xs:decimal"/>
          </xs:sequence>
        </xs:complexType>
      </xs:element>
    </xs:sequence>
    <xs:attribute name="orderid" type="xs:string" use="required"/>
  </xs:complexType>
</xs:element>
</xs:schema>

{
    "889923" : {
        "orderperson" : "John Smith",
        "shipto" : {
            "name" : "Ola Nordmann",
            "address" : "Langgt 23",
            "city" : "400 Stavanger",
            "country" : "Norway"
        },
        "items" : [
            {
                "title" : "Kittens For Beginners",
                "note" : "Special Edition",
                "quantity" : 1,
                "price" : "10.90"
            },
            {
                "title" : "Dogs For Beginners",
                "quantity" : 1,
                "price" : "9.90"
            }
        ]
    }
}

{
    "prefix" : "com.example.shipping",
    "types" : {
        "Shiporder" : {
            "ID orderid" : "",
            "REQUIRED orderperson" : "",
            "shipto" : {
                "REQUIRED name" : "",
                "REQUIRED address" : "",
                "REQUIRED city" : "",
                "country" : ""
            },
            "items" : [
                {
                    "REQUIRED title" : "",
                    "note" : "",
                    "REQUIRED quantity" : "integer",
                    "REQUIRED price" : "decimal"
                }
            ]
        }
    }
}