How to make REXML respect   (in 1.9)

Ruby
1

Rubies:

This fails on the second line…

REXML::Document.new('<b>&amp;</b>')
REXML::Document.new('<b>&nbsp;</b>')

…with Undeclared entity ’ ’

If I make that real XHTML, with a DOCTYPE and a html xmlns="…xhtml",
it
still fails.

I fixed the   itself by adding [] to the DOCTYPE.
This seems extremely tacky, because it disregards all the other fun
stuff in
XHTML.

(I suspect REXML with 1.8 did not have this issue.)

If I should call Entity.new(‘nbsp’, ’ '), I don’t understand how to .add
that before the call to .new, and I don’t understand how to easily add
new
HTML content to a preexisting Document object.

Any tips?