--- a/hotspot/agent/src/share/classes/sun/jvm/hotspot/utilities/Hashtable.java	Fri Jan 17 11:21:29 2014 -0500
+++ b/hotspot/agent/src/share/classes/sun/jvm/hotspot/utilities/Hashtable.java	Fri Jan 17 18:39:22 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2014, 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
@@ -61,8 +61,9 @@
     long h = 0;
     int s = 0;
     int len = buf.length;
+    // Emulate the unsigned int in java_lang_String::hash_code
     while (len-- > 0) {
-      h = 31*h + (0xFFL & buf[s]);
+      h = 31*h + (0xFFFFFFFFL & buf[s]);
       s++;
     }
     return h & 0xFFFFFFFFL;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/serviceability/sa/jmap-hashcode/Test8028623.java	Fri Jan 17 18:39:22 2014 +0000
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2014, 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 8028623
+ * @summary Test hashing of extended characters in Serviceability Agent.
+ * @library /testlibrary
+ */
+
+import com.oracle.java.testlibrary.JDKToolLauncher;
+import com.oracle.java.testlibrary.OutputBuffer;
+import com.oracle.java.testlibrary.ProcessTools;
+
+import java.io.File;
+
+public class Test8028623 {
+
+  public static int à = 1;
+  public static String dumpFile = "heap.out";
+
+  public static void main (String[] args) {
+
+    System.out.println(Ã);
+
+    try {
+        int pid = ProcessTools.getProcessId();
+        JDKToolLauncher jmap = JDKToolLauncher.create("jmap")
+                                              .addToolArg("-F")
+                                              .addToolArg("-dump:live,format=b,file=" + dumpFile)
+                                              .addToolArg(Integer.toString(pid));
+        ProcessBuilder pb = new ProcessBuilder(jmap.getCommand());
+        OutputBuffer output = ProcessTools.getOutput(pb);
+        Process p = pb.start();
+        int e = p.waitFor();
+        System.out.println("stdout:");
+        System.out.println(output.getStdout());
+        System.out.println("stderr:");
+        System.out.println(output.getStderr());
+
+        if (e != 0) {
+            throw new RuntimeException("jmap returns: " + e);
+        }
+        if (! new File(dumpFile).exists()) {
+            throw new RuntimeException("dump file NOT created: '" + dumpFile + "'");
+        }
+    } catch (Throwable t) {
+        t.printStackTrace();
+        throw new RuntimeException("Test failed with: " + t);
+    }
+  }
+}