xml handling in php4

given xml input as a string with a xml declaration that specifies the encoding, what can i do to always get back utf-8 data in my character data handler?

that is, how do i get "i ♥ são paulo" as utf-8 given either of these two inputs:

<?xml version="1.0" encoding="iso-8859-1"?>
<foo>i &#9829; são paulo</foo>

<?xml version="1.0"?>
<foo>i &#9829; s&#227;o paulo</foo>

handling the second case is easy, it is the first case that i can't figure out.

and someone deserves a kick in the teeth for making php4's xml parser default to iso-8859-1.