<xs:schema elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="a" xmlns:a="a" xmlns:b="b">

 <xs:element name="doc" type="a:derived"/>
 <xs:complexType name="base">
     <xs:sequence>
	<xs:element name="sub" type="a:derived2"/>
     </xs:sequence>
     <xs:attributeGroup ref="a:attG-a1"/>
 </xs:complexType>

 <xs:complexType name="derived">
    <xs:complexContent>
	<xs:extension base="a:base">
     <xs:sequence />
     <xs:attributeGroup ref="a:attG-a2"/>
	</xs:extension>
    </xs:complexContent>
 </xs:complexType>

<xs:complexType name="base2">
     <xs:sequence />
     <xs:attributeGroup ref="a:attG1-54"/>
 </xs:complexType>

 <xs:complexType name="derived2">
    <xs:complexContent>
	<xs:extension base="a:base2">
     <xs:sequence />
     <xs:attributeGroup ref="a:attG2-54"/>
	</xs:extension>
    </xs:complexContent>
 </xs:complexType>


 <xs:attribute name="attA"/>
 <xs:attributeGroup name="attG-a1">
     <xs:anyAttribute namespace="##other" processContents="lax"/>
 </xs:attributeGroup>

 <xs:attributeGroup name="attG-a2">
     <xs:anyAttribute namespace="##targetNamespace b c" processContents="lax"/>
 </xs:attributeGroup>

<xs:attributeGroup name="attG1-54">
     <xs:anyAttribute namespace="##other" processContents="lax"/>
 </xs:attributeGroup>

 <xs:attributeGroup name="attG2-54">
     <xs:anyAttribute namespace="##local b c" processContents="lax"/>
 </xs:attributeGroup>

</xs:schema>