Index: trunk/src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java	(revision 2489)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java	(revision 2490)
@@ -570,4 +570,5 @@
         EditAction editAction = new EditAction();
         propertyTable.getSelectionModel().addListSelectionListener(editAction);
+        membershipTable.getSelectionModel().addListSelectionListener(editAction);
         this.btnEdit = new SideButton(editAction);
         buttonPanel.add(this.btnEdit);
@@ -901,10 +902,18 @@
             if (!isEnabled())
                 return;
-            int row = propertyTable.getSelectedRow();
-            propertyEdit(row >= 0 ? row : 0);
+            if (propertyTable.getSelectedRowCount() == 1) {
+                int row = propertyTable.getSelectedRow();
+                propertyEdit(row);
+            } else if (membershipTable.getSelectedRowCount() == 1) {
+                int row = membershipTable.getSelectedRow();
+                membershipEdit(row);
+            }
         }
 
         protected void updateEnabledState() {
-            setEnabled(propertyTable.getSelectedRowCount() == 1);
+            setEnabled(
+                    propertyTable.getSelectedRowCount() == 1
+                    ^ membershipTable.getSelectedRowCount() == 1
+            );
         }
 
Index: trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java	(revision 2489)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java	(revision 2490)
@@ -620,9 +620,4 @@
         }
 
-        public int getIndexOfRelation(Relation relation) {
-            if (relation == null) return -1;
-            return relations.indexOf(relation);
-        }
-
         /**
          * Replies the list of selected, non-new relations. Empty list,