--- /dev/null	Mon Jan 26 16:14:30 2009
+++ new/test/java/math/BigInteger/ModPow65537.java	Mon Jan 26 16:14:29 2009
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2003 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 4891312
+ * @summary verify that modPow() not broken by the special case for 65537
+ * @author Andreas Sterbenz
+ */
+
+import java.math.BigInteger;
+import java.util.*;
+
+import java.security.*;
+import java.security.spec.*;
+
+public class ModPow65537 {
+
+    public static void main(String[] args) throws Exception {
+        // SunRsaSign uses BigInteger internally
+        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA", "SunRsaSign");
+        kpg.initialize(new RSAKeyGenParameterSpec(512, BigInteger.valueOf(65537)));
+        KeyPair kp = kpg.generateKeyPair();
+        testSigning(kp);
+
+        kpg.initialize(new RSAKeyGenParameterSpec(512, BigInteger.valueOf(65539)));
+        kp = kpg.generateKeyPair();
+        testSigning(kp);
+
+        kpg.initialize(new RSAKeyGenParameterSpec(512, BigInteger.valueOf(3)));
+        kp = kpg.generateKeyPair();
+        testSigning(kp);
+
+        // basic known answer test
+        BigInteger base = new BigInteger("19058071224156864789844466979330892664777520457048234786139035643344145635582");
+        BigInteger mod  = new BigInteger("75554098474976067521257305210610421240510163914613117319380559667371251381587");
+        BigInteger exp1 = BigInteger.valueOf(65537);
+        BigInteger exp2 = BigInteger.valueOf(75537);
+        BigInteger exp3 = new BigInteger("13456870775607312149");
+
+        BigInteger res1 = new BigInteger("5770048609366563851320890693196148833634112303472168971638730461010114147506");
+        BigInteger res2 = new BigInteger("63446979364051087123350579021875958137036620431381329472348116892915461751531");
+        BigInteger res3 = new BigInteger("39016891919893878823999350081191675846357272199067075794096200770872982089502");
+
+        if (base.modPow(exp1, mod).equals(res1) == false) {
+            throw new Exception("Error using " + exp1);
+        }
+        if (base.modPow(exp2, mod).equals(res2) == false) {
+            throw new Exception("Error using " + exp2);
+        }
+        if (base.modPow(exp3, mod).equals(res3) == false) {
+            throw new Exception("Error using " + exp3);
+        }
+
+        System.out.println("Passed");
+    }
+
+    private static void testSigning(KeyPair kp) throws Exception {
+        System.out.println(kp.getPublic());
+        byte[] data = new byte[1024];
+        new Random().nextBytes(data);
+
+        Signature sig = Signature.getInstance("SHA1withRSA", "SunRsaSign");
+        sig.initSign(kp.getPrivate());
+        sig.update(data);
+        byte[] sigBytes = sig.sign();
+
+        sig.initVerify(kp.getPublic());
+        sig.update(data);
+        if (sig.verify(sigBytes) == false) {
+            throw new Exception("signature verification failed");
+        }
+        System.out.println("OK");
+    }
+
+}