--- a/langtools/test/tools/lib/ToolBox.java	Wed Nov 05 19:12:45 2014 -0800
+++ b/langtools/test/tools/lib/ToolBox.java	Wed Nov 05 19:48:42 2014 -0800
@@ -1475,7 +1475,11 @@
                         @Override
                         public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
                             try {
-                                JarEntry e = new JarEntry(base.relativize(file).normalize().toString());
+                                String p = base.relativize(file)
+                                        .normalize()
+                                        .toString()
+                                        .replace(File.separatorChar, '/');
+                                JarEntry e = new JarEntry(p);
                                 jos.putNextEntry(e);
                                 jos.write(Files.readAllBytes(file));
                                 jos.closeEntry();