Please describe the problem:
I have the following RelaxNG Schema (but I use W3C schema types so it should be the same with a XSD):

<?xml version="1.0" encoding="UTF-8"?>
<grammar xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
  <start>
    <ref name="code"/>
  </start>
  <define name="code">
    <element name="code">
      <data type="NMTOKEN">
        <param name="minLength">2</param>
        <param name="maxLength">3</param>
        <param name="pattern">[a-z]+</param>
      </data>
    </element>
  </define>
</grammar>

And the following XML file:
<?xml version="1.0" encoding="iso-8859-1"?>
<code>  fr</code>

xmllint refuses it:

bidon.xml:2: element code: Relax-NG validity error : Error validating datatype NMTOKEN
bidon.xml:2: element code: Relax-NG validity error : Element code failed to validate content
bidon.xml fails to validate

According to XML guru Eric van der Vlist and to the standard http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/#rf-whiteSpace, it should be accepted since only xsd:string are not normalized before testing the pattern. NMTOKEN (or integers) are normalized so the above file should be accepted.

(xmllint also refuses integers with a pattern "[0-9]+" when they have trailing whitespace. For the same reason, it should accept them, IMHO)


Steps to reproduce:
1. Use the above files
2. % xmllint --noout --relaxng bidon.rng bidon.xml
3. 


Actual results:
See the above error message.


Expected results:
I would expect the XML file to be declared valid.

Does this happen every time?
Yes

Other information: