diff --git a/src/java/org/apache/commons/logging/impl/Jdk13LumberjackLogger.java b/src/java/org/apache/commons/logging/impl/Jdk13LumberjackLogger.java
index 80792b1..b099ac6 100644
--- a/src/java/org/apache/commons/logging/impl/Jdk13LumberjackLogger.java
+++ b/src/java/org/apache/commons/logging/impl/Jdk13LumberjackLogger.java
@@ -57,6 +57,14 @@ public class Jdk13LumberjackLogger implements Log, Serializable {
     private boolean classAndMethodFound = false;
 
 
+    /**
+     * This member variable simply ensures that any attempt to initialise
+     * this class in a pre-1.4 JVM will result in an ExceptionInInitializerError.
+     * It must not be private, as an optimising compiler could detect that it
+     * is not used and optimise it away.
+     */
+    protected static final Level dummyLevel = Level.FINE;
+
     // ----------------------------------------------------------- Constructors
 
 
diff --git a/src/java/org/apache/commons/logging/impl/Jdk14Logger.java b/src/java/org/apache/commons/logging/impl/Jdk14Logger.java
index ba2cb8e..56c1e1c 100644
--- a/src/java/org/apache/commons/logging/impl/Jdk14Logger.java
+++ b/src/java/org/apache/commons/logging/impl/Jdk14Logger.java
@@ -38,6 +38,13 @@ import org.apache.commons.logging.Log;
 
 public class Jdk14Logger implements Log, Serializable {
 
+    /**
+     * This member variable simply ensures that any attempt to initialise
+     * this class in a pre-1.4 JVM will result in an ExceptionInInitializerError.
+     * It must not be private, as an optimising compiler could detect that it
+     * is not used and optimise it away.
+     */
+    protected static final Level dummyLevel = Level.FINE;
 
     // ----------------------------------------------------------- Constructors