Are there known limitations to enforcing facet restrictions in xsd?

[Frosty]

Following xsd
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<?xml version="1.0" encoding="utf-8" ?><xs:schema id="EmployeesSchema" targetNamespace="http://tempuri.org/EmployeesSchema.xsd" elementFormDefault="qualified
xmlns="http://tempuri.org/EmployeesSchema.xsd" xmlns:mstns="http://tempuri.org/EmployeesSchema.xsd
xmlns:xs="http://www.w3.org/2001/XMLSchema"><xs:simpleType name="ZipCode"><xs:restriction base="xs:positiveInteger"><xs:pattern value="\d{5}" /></xs:restriction></xs:simpleType><xs:complexType name="Address"><xs:sequence><xs:element name="Name" type="xs:string" /><xs:element name="Street" type="xs:string" /><xs:element name="State" type="xs:string" /><xs:element name="Zip" type="ZipCode" /></xs:sequence></xs:complexType><xs:element name="EmployeeList"><xs:complexType><xs:sequence>< xs:element name="Employee"><xs:complexType><xs:sequence><xs:e lement name="Email" type="xs:string" /><xs:element name="Password" type="xs:string" /><xs:element name="HomeAddress" type="Address" /><xs:element name="OtherAddress" type="Address" /></xs:sequence></xs:complexType></xs:element></xs:sequence></xs:complexType></xs:element></xs:schema

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does not enforce the
<xs:pattern value="\d{5}" /

restriction.

There seem to be differences between new and older version of VS .Net on this. And using Visual Studio only to create this xsd, then creating an xml based on the xsd, followed by creating a new xsd based on this xml, does not create identical xsd as would be expected. The restriction piece is gone in the new xsd (using newest demo version of VS .NET)

Adding data to the xml using VS does not enforce the constraint, neither does a simple app with a dataset and datagrid. I have tried various facets with no luck

Rgds
O