Having an empty node is not sufficient? Note that when you delete something from the DOM that a remerge of the data and template will happen automatically ...this has caused me grief in the past (if you are getting additional data from an external source).
The command is:
xfa.datasets.data.form1.page1.nodes.remove(xfaObject to remove);
so typically the exppression is like this:
xfa.datasets.data.form1.page1.nodes.remove(xfa.resolveNode("xfa.datasets.data.form1.page1.billingMailAddr"));
Assuming you wanted to remove the billingMailAddr nodes.
Paul