How to use nsiVariant's

Hi,

If you look at the nsiVariant documentation:

http://www.xulplanet.com/references/xpcomref/ifaces/nsIVariant.html

You can see it has a lot of methods like getAsAString() that are
declared as [noscript].
This results in an empty interface in Java XPCom:

public interface nsIVariant extends nsISupports {
  String NS_IVARIANT_IID =
    "{6c9eb060-8c6a-11d5-90f3-0010a4e73d9a}";
}

How can I deal with variants in Java?
No read seems possible.
The only workaround I see is this, after a question in an Eclipse
forum:
http://www.eclipse.org/newsportal/article.php?id=43429&group=eclipse.platform.swt#43429

Is there any better workaround?

I need for adding extra information to DOM nodes.  I think the
interface I need is http://www.xulplanet.com/references/xpcomref/ifaces/nsIDOM3Node.html
and the setUserData() / getUserData() methods.  But unfortunately
nsiVariant's are used.

Thanks in advance for any light.
David