[xml] unimplemented schema block

[Aamer Akhter <aakhter gmail com>]

./xmllint --schema ~/avt/schemas/connectlib.xsd ~/avt/sandbox/connectlib.xml
Unimplemented block at ../libxml2-2.6.10/xmlschemas.c:2519

Which translates to this block in in 2.6.10:

   while ((IS_SCHEMA(child, "unique")) ||
            (IS_SCHEMA(child, "key")) || (IS_SCHEMA(child, "keyref"))) {
           TODO child = child->next;
   }

> From the xsd, it's this block that's causing the problem:

 <xs:element name="deviceInfo">
...
    <xs:key name="device">
      <xs:selector xpath="device"/>
      <xs:field xpath="@name"/>
    </xs:key>
...

All I really want to do is make sure that there is only one device
node with each value of attribute name. Is there a known workaround
for this, or has this already been added?

Thanks for any assistance.