CastRay and radar/sonar

Hi!

I have implemented the radar resource from Matt "CaptFallout" Webster and modified it a bit because in the end it will be used as a sonar. But I want to use LOS test to see if the object will show up on the radar/sonar.
This code is in onRender on the gui control (client side)

for (SimSetIterator itr(conn); *itr; ++itr) {
      // Make sure that the object is a shapebase object
      if ((*itr)->getType() & ShapeBaseObjectType) {
         ShapeBase* shape = static_cast<ShapeBase*>(*itr);
		 // Make sure that the object isn't the client
		 if (shape != control && shape->getShapeName()) {
			 // Make sure the shapebase object is a player (or Vehicle)
			if (shape->getType() & VehicleObjectType) {
				Point3F newCoord;
				// Get coords of player object
				newCoord = shape->getPosition();
         			// Find distance from point A (player object) to point B (client's player)
				VectorF shapeDir = newCoord - cObjPos;
				// Test to see if player object in range (deal with squared objects in cheap way to use non-negative value)
				F32 shapeDist = shapeDir.lenSquared();
				if (shapeDist == 0 || shapeDist > (mRadius * mRadius))
				   continue;

				// LOS
				// cObjPos = control Object position, newCoord = target object pos
				if(control->castRay(cObjPos, newCoord, &sonarBeam)) {
					// Some kind of control...
					// Like if(sonarBeam.object == shape)
				}

I would like to do some kind of LOS test. I found castRay but does it work like above? It never returns true... :( And ow do I test if the object that was hit is the same as the one I try to hit?