Google Javascript issues in Explorer 8 and Firefox

function Add_Point_Enable()
 {	
	//Allows user to add a new point to the map by clicking on the map
	alert('Move the cursor to the desired location');
	document.getElementById("datatable").style.display = "";
	document.getElementById("Cancel").disabled=false;
	map.getDragObject().setDraggableCursor("crosshair");
	GEvent.addListener(map, "click", function(marker, point) 
		{  
		 document.getElementById('currentid').value = "";
		 ChangeButtons();
			if (marker) 
			{    
				
			} 
			else 
			{    
				var confirmpoint = confirm("Do you want to add a signal to this location?");
				
				if (confirmpoint)
				{
					map.clearOverlays();
					GetData();
					map.addOverlay(new GMarker(point));
					ClearData();
					document.mapform.newlat.value = point.y;
					document.mapform.newlon.value = point.x;
					document.getElementById("Save").disabled=false;
					document.getElementById("Add").disabled=true;
					//document.getElementById("storydisplay").style.display = "none"; 
				} 
			}
		} // close of function(marker,point)
	); //close of listener
}