Index: /applications/editors/josm/plugins/jts/src/org/openstreetmap/josm/plugins/jts/JTSConverter.java
===================================================================
--- /applications/editors/josm/plugins/jts/src/org/openstreetmap/josm/plugins/jts/JTSConverter.java	(revision 35063)
+++ /applications/editors/josm/plugins/jts/src/org/openstreetmap/josm/plugins/jts/JTSConverter.java	(revision 35064)
@@ -91,5 +91,5 @@
 
         // TODO: need to check tags to determine whether area or not
-        if (way.isClosed()) {
+        if (way.isClosed() && coordSeq.size() >= 4) {
             LinearRing ring = new LinearRing(coordSeq, getGeometryFactory());
             return new Polygon(ring, null, getGeometryFactory());