Yes, you should delete the space between <? and xml.
<?xml version="1.0" encoding="utf-8" ?>
<form>
<e order="0" type="custom" name="test">
<fi type="text" />
<o />
</e>
<e order="1" type="zip" />
<e order="2" type="state" />
</form>
Here’s the relevant XML spec.