diff --git a/src/fitnesse/responders/WikiImportingTraverser.java b/src/fitnesse/responders/WikiImportingTraverser.java
index 82de46011b..ce89651ebd 100644
--- a/src/fitnesse/responders/WikiImportingTraverser.java
+++ b/src/fitnesse/responders/WikiImportingTraverser.java
@@ -89,9 +89,9 @@ public void pageImportError(WikiPage localPage, Exception e) {
   }
 
   public static class ImportError {
-    private String message;
-    private String type;
-    private Exception exception;
+    private final String message;
+    private final String type;
+    private final Exception exception;
 
     public ImportError(String type, String message) {
       this(type, message, null);
diff --git a/src/fitnesse/slim/SlimException.java b/src/fitnesse/slim/SlimException.java
index aacbc96e6a..c9f2fa10cc 100644
--- a/src/fitnesse/slim/SlimException.java
+++ b/src/fitnesse/slim/SlimException.java
@@ -3,16 +3,16 @@
 public class SlimException extends Exception {
   private static final String PRETTY_PRINT_TAG_START = "message:<<";
   private static final String PRETTY_PRINT_TAG_END = ">>";
-  private String tag;
-  private boolean prettyPrint;
+
+  private final String tag;
+  private final boolean prettyPrint;
 
   public SlimException(String message) {
-    this(message, false);
+    this(message, "", false);
   }
 
   public SlimException(String message, boolean prettyPrint) {
-    super(message);
-    this.prettyPrint = prettyPrint;
+    this(message, "", prettyPrint);
   }
 
   public SlimException(String message, String tag) {
@@ -26,12 +26,11 @@ public SlimException(String message, String tag, boolean prettyPrint) {
   }
 
   public SlimException(Throwable cause) {
-    this(cause, false);
+    this(cause, "", false);
   }
 
   public SlimException(Throwable cause, boolean prettyPrint) {
-    super(cause);
-    this.prettyPrint = prettyPrint;
+    this(cause, "", prettyPrint);
   }
 
   public SlimException(Throwable cause, String tag) {
@@ -49,8 +48,7 @@ public SlimException(String message, Throwable cause) {
   }
 
   public SlimException(String message, Throwable cause, boolean prettyPrint) {
-    super(message, cause);
-    this.prettyPrint = prettyPrint;
+    this(message, cause, "", prettyPrint);
   }
 
   public SlimException(String message, Throwable cause, String tag) {