diff --git a/core/src/main/java/net/sourceforge/jnlp/runtime/JNLPRuntime.java b/core/src/main/java/net/sourceforge/jnlp/runtime/JNLPRuntime.java
index 375f4db03..90b365492 100644
--- a/core/src/main/java/net/sourceforge/jnlp/runtime/JNLPRuntime.java
+++ b/core/src/main/java/net/sourceforge/jnlp/runtime/JNLPRuntime.java
@@ -41,7 +41,6 @@
 import net.sourceforge.jnlp.util.RestrictedFileUtils;
 import net.sourceforge.jnlp.util.logging.LogConfig;
 import net.sourceforge.jnlp.util.logging.OutputController;
-import sun.net.www.protocol.jar.URLJarFile;
 
 import javax.jnlp.ServiceManager;
 import javax.naming.ConfigurationException;
@@ -300,8 +299,6 @@ public static void initialize() throws IllegalStateException {
         Security.setProperty("package.access",
                              Security.getProperty("package.access")+",net.sourceforge.jnlp");
 
-        URLJarFile.setCallBack(CachedJarFileCallback.getInstance());
-
         initialized = true;
         LOG.debug("End JNLPRuntime.initialize()");
     }
diff --git a/core/src/main/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoader.java b/core/src/main/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoader.java
index dd3056a1b..d103ed899 100644
--- a/core/src/main/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoader.java
+++ b/core/src/main/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoader.java
@@ -46,7 +46,6 @@
 import net.sourceforge.jnlp.cache.NativeLibraryStorage;
 import net.sourceforge.jnlp.config.ConfigurationConstants;
 import net.sourceforge.jnlp.runtime.ApplicationInstance;
-import net.sourceforge.jnlp.runtime.CachedJarFileCallback;
 import net.sourceforge.jnlp.runtime.JNLPRuntime;
 import net.sourceforge.jnlp.security.AppVerifier;
 import net.sourceforge.jnlp.security.JNLPAppVerifier;
@@ -1253,7 +1252,7 @@ private Void doActivateJars(List<JARDesc> jars) {
                                     URL fileURL = new URL("file://" + extractedJarLocation);
                                     // there is no remote URL for this, so lets fake one
                                     URL fakeRemote = new URL(jar.getLocation().toString() + "!" + je.getName());
-                                    CachedJarFileCallback.getInstance().addMapping(fakeRemote, fileURL);
+                                    //CachedJarFileCallback.getInstance().addMapping(fakeRemote, fileURL);
                                     addURL(fakeRemote);
 
                                     jarLocationSecurityMap.put(new UrlKey(fakeRemote), jarSecurity);
@@ -1268,12 +1267,16 @@ private Void doActivateJars(List<JARDesc> jars) {
                     }
                 }
 
-                addURL(jar.getLocation());
+                if (localFile != null) {
+                    addURL(localFile.toURI().toURL());
+                } else {
+                    addURL(jar.getLocation());
+                }
 
                 // there is currently no mechanism to cache files per
                 // instance.. so only index cached files
                 if (localFile != null) {
-                    CachedJarFileCallback.getInstance().addMapping(jar.getLocation(), localFile.toURI().toURL());
+                    //CachedJarFileCallback.getInstance().addMapping(jar.getLocation(), localFile.toURI().toURL());
 
                     try (JarFile jarFile = new JarFile(localFile.getAbsolutePath())) {
                         JarIndexAccess index = JarIndexAccess.getJarIndex(jarFile.getNative());
@@ -1282,7 +1285,7 @@ private Void doActivateJars(List<JARDesc> jars) {
                         }
                     }
                 } else {
-                    CachedJarFileCallback.getInstance().addMapping(jar.getLocation(), jar.getLocation());
+                    //CachedJarFileCallback.getInstance().addMapping(jar.getLocation(), jar.getLocation());
                 }
 
                 LOG.debug("Activate jar: {}", location);
@@ -1573,9 +1576,12 @@ private void addNewJar(final JARDesc desc, UpdatePolicy updatePolicy) {
                 return null;
             });
 
-            addURL(remoteURL);
-            CachedJarFileCallback.getInstance().addMapping(remoteURL, cachedUrl);
-
+            File localFile = tracker.getCacheFile(remoteURL);
+            if (localFile != null) {
+                addURL(remoteURL.toURI().toURL());
+            } else {
+                addURL(remoteURL);
+            }
         } catch (Exception e) {
             // Do nothing. This code is called by loadClass which cannot
             // throw additional exceptions. So instead, just ignore it.
diff --git a/core/src/test/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoaderTest.java b/core/src/test/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoaderTest.java
index e2ef884e7..2e58ac779 100644
--- a/core/src/test/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoaderTest.java
+++ b/core/src/test/java/net/sourceforge/jnlp/runtime/classloader/JNLPClassLoaderTest.java
@@ -84,7 +84,6 @@
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 @NotThreadSafe
 @Ignore
@@ -555,7 +554,6 @@ public void testLoadClass() throws Exception {
         JNLPRuntime.setSecurityEnabled(false);
         JNLPRuntime.setDebug(true);
         getConfiguration().setProperty(ConfigurationConstants.KEY_ENABLE_MANIFEST_ATTRIBUTES_CHECK, "NONE");
-        URLJarFile.setCallBack(CachedJarFileCallback.getInstance());
 
         final ServerLauncher as = ServerAccess.getIndependentInstance(jnlp.getParent(), port);
         try {
@@ -569,7 +567,6 @@ public void testLoadClass() throws Exception {
             JNLPRuntime.setSecurityEnabled(securityBackup);
             JNLPRuntime.setDebug(verbose);
             getConfiguration().setProperty(ConfigurationConstants.KEY_ENABLE_MANIFEST_ATTRIBUTES_CHECK, manifestAttsBackup);
-            URLJarFile.setCallBack(null);
             as.stop();
 
             clearCache();