[news.eclipse.webtools] Importing a schema into another schema: "invalid

[Mauro Molinari <mauro.molinari@xxxxxxxxxxxx>]

Hello all!

I'm editing the inline schema of a WSDL and I tried to add an import 
directive to import another schema I defined on a stand-alone XSD file.

This file is well-formed and valid (no validation errors given by 
Eclipse), but in the import wizard dialog, when I try to select it from 
the workspace (step named "Select XML schema file"), as soon as I click 
on it an error hint is given: "filename.xsd is an invalid XML schema 
file". The "Finish" button is grayed out and I cannot import it...

I'm quite new to WSDL and XSD, I'm learning now... anyone could help me 
to determine the source of the problem?

The XSD I'm trying to import is the following:

<?xml version="1.0" encoding="UTF-8"?>
<schema
  targetNamespace="http://webservice.cardinis.com/AccessServices/xsd";
  elementFormDefault="qualified"
  xmlns="http://www.w3.org/2001/XMLSchema";
  xmlns:tns="http://webservice.cardinis.com/AccessServices/xsd";>
  <annotation>
    <documentation>
      Schema per la definizione dei tipi usati dal webservice di
      autenticazione.
    </documentation>
  </annotation>

  <element name="Login_Username" type="string">
    <annotation>
      <documentation>
        Parametro d'ingresso relativo al nome utente nell'operazione di
        login.
      </documentation>
    </annotation>
  </element>

  <element name="Login_Password" type="string">
    <annotation>
      <documentation>
        Parametro d'ingresso relativo alla password nell'operazione di
        login.
      </documentation>
    </annotation>
  </element>

  <element name="Login_Ticket" type="string">
    <annotation>
      <documentation>
        Parametro di uscita relativo al ticket assegnato all'utente
        dall'operazione di login.
      </documentation>
    </annotation>
  </element>
</schema>

Thanks in advance.

Mauro.