Overview Map not working with ka-map layer

[openlayers]

I am trying to get an overview map of my ka-map layer but it seems to be creating some strange behaviour. The overview map control is added, but no map is displayed - in addition the MouseDefaults seem to be a little funky - the map doesn't stop panning and also if you change to the zoom tool it continues to draw zoom rectangles without updating. I have included my code below:

map = new OpenLayers.Map('map',{'controls':[],'maxResolution': 'auto', 'units':'m',
				'maxExtent': new OpenLayers.Bounds(498576,98018,501079,101042 ), 
				'scales': [10000,5000,2000,1000,500,250,100,50,20,10],
				'tileSize': new OpenLayers.Size(150,150)});

            var kamap = new OpenLayers.Layer.KaMap( "ARK Map",
                    "https://my.path.to.tile.php", {g: "ARKMap", map: "klarent", i: "ALPHA"});

//now lets setup the overview map 

var options = {'mapOptions': {'maxResolution': 'auto',
 'units':'m', 
  'maxExtent': new OpenLayers.Bounds (498576,98018,501079,101042),
  'minRatio':8,	
  'maxRatio':32,									  'layers':[kamap.clone()]} };

ov_map = new OpenLayers.Control.OverviewMap(options);

			ov_map.isSuitableOverview = function() {
                                          return false;
           };

             map.addLayers([kamap]);       
	     map.addControl(new OpenLayers.Control.PanZoomBar());
             map.addControl(new OpenLayers.Control.MouseToolbar());
 	     map.addControl(new OpenLayers.Control.Scale());
             map.addControl(new OpenLayers.Control.MousePosition());
             map.addControl(ov_map);

[tschaub]

As far as I can tell, this was resolved with r3087.