Can you add this wms into your app ?
http://212.26.144.110/geowebcache/service/wms?tiled=true&LAYERS=kadastr&STYLES=&FORMAT=image%2Fpng&TRANSPARENT=true&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&SRS=EPSG%3A900913&
map http://212.26.144.110/kadastrova-karta
LAYER kadastr
In your case, if you have only few polygons
I will use ArcGIS Topolygy tools, and assign manualy atributes of overlapping.
if you have many polygons
I recommend you to use ArcGIS Tool "AnalysisTools">"Overlay˙">"Intersect". You will revive overlapping poligons