Components.classes["@mozilla.org/psm;1"].getService()

"Petar Popara" <[email protected]> Tue, 14 Jun 2005 09:57:20 +0200

Newsgroups	gmane.comp.mozilla.devel.xpinstall
Organization	Another Netscape Collabra Server User
Message-ID	<[email protected]>

I'm trying to call this from JavaScript:

Components.classes["@mozilla.org/psm;1"].getService();

but, I got this error:

http://xulplanet.com/tutorials/xulqa/q_pdenyucc.html

Is there a way to add this code into my Firefox (C++) plugin and not to call 
it from JavaScript?