Problem with declaring vertex normals

[chris_jan]

Hello,
I'm programming a small game with BulletPhysics and OpenGL (2.1).
Yesterday I added lighting to the game, so I needed normals for the objects, too.
But I've got a problem with that:
I'm creating a cuboid with the following code:

m_vVertices.pObj = new CVector3D[8];
GLfloat corners[] = {-vHalfExtents.x, vHalfExtents.y, vHalfExtents.z,
		vHalfExtents.x, vHalfExtents.y, vHalfExtents.z,
		vHalfExtents.x, -vHalfExtents.y, vHalfExtents.z,
		-vHalfExtents.x, -vHalfExtents.y, vHalfExtents.z,
		-vHalfExtents.x, vHalfExtents.y, -vHalfExtents.z,
		vHalfExtents.x, vHalfExtents.y, -vHalfExtents.z,
		vHalfExtents.x, -vHalfExtents.y, -vHalfExtents.z,
		-vHalfExtents.x, -vHalfExtents.y, -vHalfExtents.z};
for (int i = 0; i < 8; ++i)
{
	m_vVertices.pObj[i].x = corners[i*3];
	m_vVertices.pObj[i].y = corners[i*3+1];
	m_vVertices.pObj[i].z = corners[i*3+2];
}
 
m_VertexIndices.pObj = new GLuint[6*4];
GLubyte indices[] = {0, 1, 2, 3,
		4, 5, 1, 0,
		3, 2, 6, 7,
		5, 4, 7, 6,
		1, 5, 6, 2,
		4, 0, 3, 7};
for (int i = 0; i < 24; ++i)
{
	m_VertexIndices.pObj[i] = indices[i];
}

Later, I'm rendering with this code:

glEnableClientState(GL_VERTEX_ARRAY);
 
glVertexPointer(3, GL_FLOAT, 0, static_cast<void*>(m_vVertices.pObj));
glDrawElements(GL_QUADS, 24, GL_UNSIGNED_INT,
		static_cast<void*>(m_VertexIndices.pObj));
 
glDisableClientState(GL_VERTEX_ARRAY);

But when I wanted to add normals, I had a problem: As far as I know OpenGL doesn't support surface normals, only vertex normals.
But because I'm reusing shared vertices with the help of an index array, I can't specify normals per vertex beacause - dependent on which face a vertex belongs to - each vertex can have different normals. Is there a way I can still use indices to specify the order of the vertices drawn or do I have to declare shared vertices multiple times (for every face needed)?

Thank you for your answers in advance!