Error in Validating with Schema and in generating sample XML from it !!! Schema is valid in XML Spy 5.0 . Namespace problems.

Hello,

I have 3 big xsd files. The problem is that I cann't validate an xml sample using JAXP1.2. Also I tryed with JAXB and Castor but seems to be the same problem.

I made an simple example in 3 files that generate the error:
1.xsd - this is the main file

<?xml version="1.0" encoding="UTF-8"?><xsd:schema targetNamespace="http://www.example.com/response" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:fmcg="http://www.example.com/fmcg" xmlns:core="http://www.example.com/core" xmlns="http://www.example.com/response" elementFormDefault="qualified" attributeFormDefault="unqualified">	<xsd:import namespace="http://www.example.com/fmcg" schemaLocation="2.xsd"/>	<xsd:element name="response" type="ResponseType"/>	<xsd:complexType name="ResponseType">		<xsd:sequence>			<xsd:element name="senderName" type="xsd:string"/>			<xsd:element ref="fmcg:item" minOccurs="0" maxOccurs="unbounded"/>		</xsd:sequence>	</xsd:complexType></xsd:schema>
2.xsd 

<?xml version="1.0" encoding="UTF-8"?><xsd:schema targetNamespace="http://www.example.com/fmcg" xmlns:core="http://www.example.com/core" xmlns="http://www.example.com/fmcg" xmlns:fmcg="http://www.example.com/fmcg" xmlns:xsd="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">	<xsd:import namespace="http://www.example.com/core" schemaLocation="3.xsd"/>	<xsd:element name="item" type="ItemType"/>	<xsd:complexType name="ItemType">		<xsd:complexContent>			<xsd:extension base="core:ItemType">				<xsd:sequence>					<xsd:element name="itemName" type="xsd:string"/>				</xsd:sequence>			</xsd:extension>		</xsd:complexContent>	</xsd:complexType></xsd:schema>
3.xsd

<?xml version="1.0" encoding="UTF-8"?><xsd:schema targetNamespace="http://www.example.com/core" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://www.example.com/core" elementFormDefault="unqualified" attributeFormDefault="unqualified">	<xsd:complexType name="ItemType" abstract="true">		<xsd:sequence>			<xsd:element name="additionalItemName" type="xsd:string" minOccurs="0"/>		</xsd:sequence>	</xsd:complexType></xsd:schema>
And this is a sample xml file:

<?xml version="1.0" encoding="UTF-8"?><response xmlns="http://www.example.com/response" xmlns:core="http://www.example.com/core" xmlns:fmcg="http://www.example.com/fmcg"  >	<senderName>String</senderName>	<fmcg:item>		<core:additionalItemName>String</core:additionalItemName>		<fmcg:itemName>String</fmcg:itemName>	</fmcg:item></response>
This files was all validated with Schema by XML Spy 5.0.
When I try to validate this XML file with JAXP1.2
I got this ERROR: (file:test.xml: 7, 28): cvc-complex-type.2.4.a: Invalid content starting with element 'core:additionalItemName'. One of '{"":additionalItemName, "http://www.example.com/fmcg":itemName}' is expected. 
It seems that the parser expects 'additionalItemName' instead of 'core:additionalItemName'. 
Why ? I think the namespace is OK.(Also I tryed with Castor and JAXB and seems to have the same error).

Also I tryed to generate a XSD schema with XML Spy 5.0 from the sample XML file but the Schema generated was INVALID.
Why is something wrong with my files? 
Can I write a simple XSD file(just 1 file - not 3 files as above) that validate my XML file ?


Regards,
Catalin