Actually, just remove the colon and the prefix entirely. It becomes surprisingly readable:

    <object xsi:schemaLocation="http://www.datapower.com/schemas/json jsonx.xsd"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns="http://www.ibm.com/xmlns/prod/2009/jsonx">
        <string name="name">John Smith</string>
        <object name="address">
            <string name="streetAddress">21 2nd Street</string>
            <string name="city">New York</string>
            <string name="state">NY</string>
            <number name="postalCode">10021</number>
        </object>
        <array name="phoneNumbers">
            <string>212 555-1111</string>
            <string>212 555-2222</string>
        </array>
        <null name="additionalInfo" />
        <boolean name="remote">false</boolean>
        <number name="height">62.4</number>
        <string name="ficoScore"> > 640</string>
    </object>