[xml] exc c14n w/o comments bug

[Tomas Sieger <tomas sieger systinet com>]

Hi,
 I found another "mutation" of the bug I already reported several weeks 
ago: multiple namespace declaration in the output of the exclusive c14n 
w/o comments.

This time, the bug is really serious. Even libxml2 can't parse its own 
output :-))).

You can reproduce the bug using the attached files.

Run:

  ./testC14N --exc-without-comments b.xml b.xpath

I can see this output:

<wn1:ticket
xmlns:i="http://www.w3.org/2001/XMLSchema-instance"; 
xmlns:i="http://www.w3.org/2001/XMLSchema-instance"; 
xmlns:wn0="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"; 
xmlns:wn1="http://xmlsoap.org/Ping"; wn0:Id="Id-Ticket1" i:nil="true" 
i:type="wn1:ticketType"></wn1:ticket>

Note the "i" namespace is declared for two times!

regards,
 Tomas

<?xml version="1.0" encoding="UTF-8"?>
<e:Envelope xmlns:d="http://www.w3.org/2001/XMLSchema"; xmlns:e="http://schemas.xmlsoap.org/soap/envelope/"; 
xmlns:i="http://www.w3.org/2001/XMLSchema-instance"; 
xmlns:wn0="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"; 
xmlns:wn1="http://xmlsoap.org/Ping";>
  <e:Body xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"; 
wsu:Id="Body-Id-9e6a3de0-9dd4-11d8-befa-994b8300befa">
    <wn1:Ping i:type="wn1:ping">
      <wn1:ticket wn0:Id="Id-Ticket1" i:nil="true" i:type="wn1:ticketType"/>
      <wn1:text i:type="d:string">Systinet - Scenario #5</wn1:text>
    </wn1:Ping>
  </e:Body>
</e:Envelope>

<XPath xmlns:wn1="http://xmlsoap.org/Ping";>
(//. | //@* | //namespace::*)[ancestor-or-self::wn1:ticket]
</XPath>