Help needed with scene graph reorganization

I ran into a problem with my game engine I am building that uses a scene graph. Mainly that if I want an object to be draw over another object the object on top must be added to the scene graph after the object on bottom. (Note: This is logical and perfectly acceptable behavior for a scene graph)

To make this simpler I added the idea of draw layers, so that the scene graph would be reorganized so that the lowest draw layers are added first and the highest draw layers are added last.

I figured out a way to do this quite easily (or so I thought), however I ran across a strange problem that caused the program to enter an endless loop.

Eventually I discovered that this was because the nodes were being copied into the new tree directly, which was as I had programed it, this caused the last node of the new scene graph to often point to a node listed earlier in the graph thereby causing an infinite loop.

I then came up with a genius idea, at least it seemed like it at the time, to clear the nodes of their pointer to the next node in the scene graph. However as many of you probably have realized by now if I am only passing pointers of the nodes around then that method directly clears the node itself and causing the old scene graph to be broken in such a way that the reorganization cannot continue.

So I am now thoroughly stumped on what to do and need any suggestions or help that this community can give. Below you can find my own attempt at doing this.

Please note, however, that I copied it directly out of my source code and that it was commented out due to sheer frustrated so it quite likely has a number of errors that I introduced trying to fix it.

Any help would earn my deepest thanks,
-BenV

void ScreenObject::ReorganizeSceneGraph(void)
{
	SceneObject *m_pRootNewGraph = 0;

	int reordered = 0;
	int curdraworder = m_iLowestDrawLayer;

	while(reordered < m_iNumObjects)
	{
		SceneObject *pObject = 0;
		pObject = m_pRootObj;
		while(pObject)
		{
			if(reordered < m_iNumObjects)
			{
				if(pObject->GetDrawLayer()==curdraworder)
				{
					if(&m_pRootNewGraph == NULL)
					{
						m_pRootNewGraph = pObject;
						m_pRootNewGraph.ClearHierarchy();
					}
					else
					{
						SceneObject *nObj = pObject;
						nObj->ClearHierarchy();
						SceneObject* pObj = m_pRootNewGraph;
						while(pObj->GetNext())
						{
							pObj = pObj->GetNext();
						}
						pObj->AddAfter(nObj);
					}
					reordered++;
				}
				pObject = pObject->GetNext();
			}
			else
			{
				pObject = NULL;
			}
		}
		curdraworder++;
	}

	//Copy the new graph
	m_iNumObjects = 0;
	m_pRootObj = m_pRootNewGraph;
}