(PHP 4.2) This function replaces the child oldnode with the passed new node. If
the new node is already a child it will not be added a second
time. If the old node cannot be found the function returns
FALSE. If the replacement
succeds the old node is returned.
(PHP 4.3) This function replaces the child oldnode with the passed newnode, even if the new node already
is a child of the DomNode. If
newnode was already inserted in the document it is
first unlinked from its existing context. If the old node
cannot be found the function returns
FALSE. If the replacement succeds the old node is
returned. (This behaviour is according to the W3C specs).
See also
domnode_append_child()