accessors for publicId / systemId from a loaded DTDGrammarType Grammar ?

[Ben Griffin]

Having loaded an arbitrary DTDGrammar, is there a way of being able to  
access the publicId or systemId for that Grammar?

I have loaded the grammar up as follows..
Grammar* g = myDOMLSParser->loadGrammar(myDOMLSInput,  
Grammar::DTDGrammarType, true);

What I want to know is what the publicId / systemId is of Grammar g.
Any ideas or suggestions?