Hello,

I'm currently working with the following schema and I can't seem to get it
to validate. I don't see a problem with it and was wondering if anyone had any idea why this schema is invalid. The following is the smallest part of the schema which produces the validation problem using xerces.

ERROR: Line 33: derivation-ok-restriction2.1.2: Error for type 'ycjbt6fq'
The attribute use 'n12zldi9' in this type has 'null', which is not validly derived from 'null', the type of the matching attribute use in this base type.

<xs:schema targetNamespace="http://targetnamespace.com"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:test="http://targetnamespace.com">

<xs:complexType name="CT1">
<xs:complexContent>
<xs:restriction base="xs:anyType" />
</xs:complexContent>
</xs:complexType>

<xs:complexType name="CT2">
<xs:complexContent>
<xs:extension base="test:CT1">
<xs:attribute id="la1488304683" name="nl2zldi9">
<xs:simpleType>
<xs:restriction base="xs:integer">
<xs:minInclusive fixed="false"
value="-2147483217" />
</xs:restriction>
</xs:simpleType>
</xs:attribute>
</xs:extension>
</xs:complexContent>
</xs:complexType>

<xs:complexType name="ycjbt6fq">
<xs:complexContent>
<xs:restriction base="test:CT2">
<xs:attribute name="nl2zldi9">
<xs:simpleType>
<xs:restriction base="xs:integer">
<xs:minInclusive fixed="false"
value="-2147483217" />
</xs:restriction>
</xs:simpleType>
</xs:attribute>
</xs:restriction>
</xs:complexContent>
</xs:complexType>
</xs:schema>