Problem with libxml2

[Adalberto Gonçalves]

Hello, I'm sorry contacting directly you, but I'm not sure where to go to.
I've got a problem with LIBXML. It seens it's not parsing the regular
I have the following type in the .XSD:
<xs:simpleType name="TString">
 <xs:annotation>
<xs:documentation> Tipo string genérico</xs:documentation>
 </xs:annotation>
 <xs:restriction base="xs:string">
<xs:whiteSpace value="preserve"/>
 <xs:pattern value="[!-ÿ]{1}[ -ÿ]{0,}[!-ÿ]{1}|[!-ÿ]{1}"/>
 </xs:restriction>
</xs:simpleType>
And I can't assign a string with 2 characters. It's allowed 1, 3 or
more. But as far as I can see, the expression allows 2. The erros are:
Error 1839: [facet 'pattern'] The value 'XX' is not accepted by the
pattern
Error 1824: 'XX' is not a valid value of the local atomic type.
I'd appreciate any help on how to solve this or the right place to
report the problem.

Thank you very much!