(PHP 4.2) This function replaces an existing node with
the passed new node. Before the replacement newnode is copied if it has a parent
to make sure a node which is already in the document will not
be inserted a second time. This behaviour enforces doing all
modifications on the node before the replacement or to
refetch the inserted node afterwards with functions like domnode_first_child(), domnode_child_nodes() etc..
(PHP 4.3) This function replaces an existing node with
the passed new node. It is not copied anymore. If newnode was already inserted in the
document it is first unlinked from its existing context. If
the replacement succeds the old node is returned.
See also
domnode_append_child()