Unmarshaling XML document with no namespace declarations

Given a schema that has a target namespace, such as the example shown below,

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://ift.tt/tphNwY" elementFormDefault="qualified" targetNamespace="http://ift.tt/1Drc5QB" xmlns:messaging="http://ift.tt/1Drc5QB">
  <xs:element name="Customer">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="messaging:CustAddress"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="CustAddress">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="messaging:AddressLine"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="AddressLine" type="xs:string"/>
</xs:schema>

How do I unmarshall a XML instance that does not have any namespaces, such as this one:

<?xml version="1.0" encoding="UTF-8"?>
<Customer>
    <CustAddress>
        <AddressLine>Address Line 1</AddressLine>
    </CustAddress>
</Customer>

I keep running into error: file:/C:/customer.xml; lineNumber: 2; columnNumber: 11; cvc-elt.1: Cannot find the declaration of element 'Customer'

Is there anyway to be able to unmarshall this XML? While I do not have control over how the XML is generated, I can modify the schema if needed.

Thanks Aspi