Index: trunk/src/org/openstreetmap/josm/actions/JoinAreasAction.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/JoinAreasAction.java	(revision 15883)
+++ trunk/src/org/openstreetmap/josm/actions/JoinAreasAction.java	(revision 15884)
@@ -1447,5 +1447,5 @@
         for (WayInPolygon way : ways) {
             actionWays.add(way.way);
-            if (oldest.isNew() || !way.way.isNew() && oldest.getUniqueId() > way.way.getUniqueId()) {
+            if (oldest.isNew() || (!way.way.isNew() && oldest.getUniqueId() > way.way.getUniqueId())) {
                 oldest = way.way;
                 oldestPos = actionWays.size() - 1;