I was reading the schematron spec today and my eyes went crossed. It would seem that the schematron schema for schematron is not valid XML. It has two well-formed bugs. Both in the following <pattern>...
<sch:pattern abstract="true" name="requiredAttribute>
<sch:rule context=" $context ">
<sch:assert test="string-length( $attribute ) > 0">
The <sch:name/> element should have a
<sch:value-of select="$attribute /name()" /> attribute.
</sch:assert>
</sch:pattern>
Note the name atttribute-value of pattern is not closed by a quote and the rule element isn't closed either. A validation bug in a validation spec :)
Randy