If this attribute was explicity set in the XML source for the parent
element or it is a default value in the DTD (currently not supported by
phpXD) specified is true.
DOM-Level 1
Inserts the Node object $newChild into the child list of the parent node;
The $refChild parameter allows you to specify where to insert the new
node; If $refChild is null, newChild is inserted at the end of the child
list; If $newChild is linked into the document tree, it is removed before
it is inserted in its new position.
DOM-Level 1
Replaces the child node $oldChild with $newChild; If $newChild is linked
into the document tree, it is removed before the replace is performed.
DOM-Level 1
Changes the prefix of this node; For ELEMENT_NODE and ATTRIBUTE_NODE
type nodes, changing the namespace prefix also affects the nodeName,
tagName and name attributes.
DOM-Level 2