[xsl] DTD extends XML attributes, how can I suppress this behaviour

[NK <nesslegg@xxxxxxxxx>]

Hi
I have an XML that looks has a DTD that I transform with an identity template.
 <xsl:template match="node()|@*">
       <xsl:copy>
       <xsl:apply-templates select="@*"/>
       <xsl:apply-templates/>
       </xsl:copy>
 </xsl:template>

Source XML:
<?xml version ="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE ONIXMessage SYSTEM
"http://www.editeur.org/onix/2.1/reference/onix-international.dtd";>
<ONIXMessage>
<Header>
<FromCompany>Company </FromCompany>
<FromPerson>Name</FromPerson>
<FromEmail>email</FromEmail>
</Header>
.....

when I transform it, all elements get extended with attributes like shown below

<Header refname="Header" shortname="header">
<FromCompany refname="FromCompany" shortname="m174">Company</
FromCompany>
<FromPerson refname="FromPerson" shortname="m175">Name</FromPerson>
<FromEmail refname="FromEmail" shortname="m283">email</FromEmail>
</Header>

Is there a way to supress this behaviour in the stylesheet? I am using
Saxon 9b and XSLT 2.0.
If i remove the DTD from the source, it won't to that (of course).
However I don't want to do this.

thanks
Christoph