# File rexml/parent.rb, line 82
  def insert_before( child1, child2 )
			if child1.kind_of? String
				child1 = XPath.first( self, child1 )
				child1.parent.insert_before child1, child2
			else
				ind = index(child1)
				@children[ind,0] = child2
				child2.parent = self
			end
			self
		end