DOCTYPE specified but DTD not available

I have a case where the XML file has specified the DOCTYPE
<!DOCTYPE mgt-message SYSTEM "C:\cs.dtd">

and I do not have the cs.dtd.

When I am trying to parse the file using th DOM parser, with ValScheme set to "Val_Never", I am unable to get any elements. If the <!DOCTYPE ...> is removed, then it works allright. 

Any ideas as to how can I parse an XML file which has the <!DOCTYPE ....> specified but the DTD is not available ?

Thanks

-Sudhir