Fix for XMLSCHEMA-33

[Michael Pigott]

Hi everyone,
    Last week I filed https://issues.apache.org/jira/browse/XMLSCHEMA-33
and I provided a fix for it in https://github.com/mikepigott/ApacheXmlSchema
.
    I'm sorry, this is my first attempt to contribute to an Apache project.
 Are there guidelines I should follow?

Thanks!
Mike