--- a/flys-client/src/main/java/de/intevation/flys/client/client/ui/ParameterList.java	Fri Oct 19 09:20:52 2012 +0200
+++ b/flys-client/src/main/java/de/intevation/flys/client/client/ui/ParameterList.java	Fri Oct 19 09:29:57 2012 +0200
@@ -66,6 +66,8 @@
              HasParameterChangeHandler, CollectionChangeHandler,
              OutputModesChangeHandler, AdvanceHandler
 {
+    private static final long serialVersionUID = 5204784727239299980L;
+
     public static final String STYLENAME_OLD_PARAMETERS = "oldParameters";
 
     /** The message class that provides i18n strings.*/
@@ -355,6 +357,8 @@
         widget.setContainer(helperPanel);
 
         handler.addStepForwardHandler(new StepForwardHandler() {
+            private static final long serialVersionUID = -6210719844707004860L;
+
             @Override
             public void onStepForward(StepForwardEvent event) {
                 lockUI();
@@ -366,8 +370,8 @@
                 String module = moduleItems[0].getStringValue();
                 String river  = riversItems[0].getStringValue();
 
-                if (module == null) {
-                    // TODO throw / show error!
+                if (module == null || river == null) {
+                    GWT.log("ParameterList.renderNew(): module == null || river == null");
                     unlockUI();
                     return;
                 }
@@ -387,7 +391,7 @@
                         public void onFailure(Throwable caught) {
                             unlockUI();
                             GWT.log("Could not create the new artifact.");
-                            SC.warn(MSG.getString(caught.getMessage()));
+                            SC.warn(FLYS.getExceptionString(MSG, caught));
                         }
 
                         @Override