--- a/jdk/src/windows/classes/java/net/PlainSocketImpl.java	Wed Oct 02 15:31:35 2013 +0900
+++ b/jdk/src/windows/classes/java/net/PlainSocketImpl.java	Wed Oct 02 09:21:02 2013 +0100
@@ -191,14 +191,17 @@
     }
 
     protected synchronized void accept(SocketImpl s) throws IOException {
-        // pass in the real impl not the wrapper.
-        SocketImpl delegate = ((PlainSocketImpl)s).impl;
-        delegate.address = new InetAddress();
-        delegate.fd = new FileDescriptor();
-        impl.accept(delegate);
-
-        // set fd to delegate's fd to be compatible with older releases
-        s.fd = delegate.fd;
+        if (s instanceof PlainSocketImpl) {
+            // pass in the real impl not the wrapper.
+            SocketImpl delegate = ((PlainSocketImpl)s).impl;
+            delegate.address = new InetAddress();
+            delegate.fd = new FileDescriptor();
+            impl.accept(delegate);
+            // set fd to delegate's fd to be compatible with older releases
+            s.fd = delegate.fd;
+        } else {
+            impl.accept(s);
+        }
     }
 
     void setFileDescriptor(FileDescriptor fd) {

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/net/PlainSocketImpl/CustomSocketImplFactory.java	Wed Oct 02 09:21:02 2013 +0100
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8024952
+ * @summary ClassCastException in PlainSocketImpl.accept() when using custom socketImpl
+ * @run main/othervm CustomSocketImplFactory
+ */
+
+import java.net.*;
+import java.io.*;
+
+public class CustomSocketImplFactory implements SocketImplFactory {
+
+    @Override
+    public SocketImpl createSocketImpl() {
+        try {
+            SocketImpl s = new CustomSocketImpl();
+            System.out.println("Created " + s);
+            return s;
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+
+        Socket.setSocketImplFactory(new CustomSocketImplFactory());
+        try (ServerSocket ss = new ServerSocket(0)) {
+            ss.setSoTimeout(1);
+            ss.accept();
+            System.out.println("PASS");
+        } catch (SocketTimeoutException | NullPointerException e) {
+            // Not a real socket impl
+        }
+    }
+
+    class CustomSocketImpl extends SocketImpl {
+
+        public void create(boolean stream) throws IOException {
+        }
+
+        public void connect(String host, int port) throws IOException {
+        }
+
+        public void connect(InetAddress addr, int port) throws IOException {
+        }
+
+        public void connect(SocketAddress addr, int timeout) throws IOException {
+        }
+
+        public void bind(InetAddress host, int port) throws IOException {
+        }
+
+        public void listen(int backlog) throws IOException {
+        }
+
+        public void accept(SocketImpl s) throws IOException {
+        }
+
+        public InputStream getInputStream() throws IOException {
+            return null;
+        }
+
+        public OutputStream getOutputStream() throws IOException {
+            return null;
+        }
+
+        public int available() throws IOException {
+            return 0;
+        }
+
+        public void close() throws IOException {
+        }
+
+        public void sendUrgentData(int data) throws IOException {
+        }
+
+        public Object getOption(int i) throws SocketException {
+            return null;
+        }
+
+        public void setOption(int i, Object o) throws SocketException {
+        }
+    }
+}