Help with this sample

Hi,

I am trying to validate some xml against the following, In the attached
files i have:

bl.xml:

<?xml version="1.0" encoding="utf-8"?>
<TypeValidation xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'
xsi:schemaLocation='http://www.blexample.com bl.xsd'
xmlns='http://www.blexample.com'>
<birthTime>4444</birthTime>
<correct>true</correct>
<telecom>+93242345</telecom>
<telecom>1011101010101010</telecom>
<addr>
    <city>test</city>  <--------------- PROBLEM
</addr>
</TypeValidation>


bl.xsd:

<?xml version="1.0" encoding="utf-8" ?>
<xs:schema targetNamespace="http://www.blexample.com"
xmlns="http://www.blexample.com"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:hl7="http://www.blexample.com"
elementFormDefault="qualified">
<xs:include schemaLocation="../dt/bldatatypes.xsd" />
<xs:element name="TypeValidation">
<xs:complexType>
<xs:annotation>
<xs:appinfo>
<p>this is a test</p>
<diff>PQ</diff>
</xs:appinfo>
</xs:annotation>
<xs:sequence>
<xs:element name="birthTime" type="TS" minOccurs="0" maxOccurs="1" />
<xs:element name="correct" type="BL" minOccurs="0" maxOccurs="1" />
<xs:element name="telecom" type="TEL" minOccurs="0" maxOccurs="1" />
<xs:element ref="addr"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="addr">
<xs:complexType>
<xs:sequence>
<xs:element name="addr" type="AD" minOccurs="0" maxOccurs="1" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>

My question is with regards to the AD type which is defined in
bldatatypes.xsd, when I try
something like:

<addr>
    <city>xxcx</city>
</addr>

my xml will not validate, from the definition in bldatatypes.xsd I thought
this should be possible...
the error is  The active schema does not support the element 'city'.

eg:

<xs:complexType name="AD" mixed="true">
<xs:annotation>
<xs:documentation>
Mailing and home or office addresses. A sequence of address parts,
such as street or post office Box, city, postal code, country, etc.
</xs:documentation>
</xs:annotation>
<xs:sequence>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element name="delimiter">
<xs:complexType mixed="true">
<xs:complexContent mixed="true">
<xs:restriction base="ADXP">
<xs:element name="city">
<xs:complexType mixed="true">
<xs:complexContent mixed="true">
<xs:restriction base="ADXP">
<xs:attribute name="partType" type="cs_AddressPartType" fixed="CTY"/>
</xs:restriction>
</xs:complexContent>
</xs:complexType>
</xs:element>
etc........

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