I'm trying to get the RT3DApp to use the accelerometer for camera rotation. I've gotten this far:

In MyAppDelegate.mm (didAccelerate) I changed:
[[UIAccelerometer sharedAccelerometer] setDelegate:self];
[[UIAccelerometer sharedAccelerometer] setUpdateInterval:0.25f];
in FPSControlComponent::OnAdd I added:
GetBaseApp()->m_sig_accel.connect(1, boost::bind(&FPSControlComponent::OnAccel, this, _1));
void FPSControlComponent::OnAccel(VariantList *pVList)
	CL_Vec3f v = pVList->Get(1).GetVector3();

#ifdef _DEBUG
	LogMsg("Acc: %f, %f, %f", v.x, v.y, v.z);
// at some point, I should be able to set the rotation matrix, but I'm not sure how to do this
	irr::scene::CCameraSceneNode *camera = (irr::scene::CCameraSceneNode*)GetIrrlichtManager()->GetScene()->getActiveCamera(); 
	// camera->setRotation(...);
I know this is somewhat elementary matrix math, but it's been a while. How can I turn the accelerometer vector into a 3D camera rotation?