How to call JavaScript code from C++ XPCOM object

[navneet kumar]

I have written a C++ XPCOM object. I would like to call a javascript 
function from this object. JavaScript function is defined in html page 
hosting XPCOM object.

In other words, I am looking for something equivalent to the following in IE
                 pIHTMLWindow->execScript(bstrScript,NULL,&vtResult);

where bstrScript has JavaScript function name defined in html page.

Navneet