--- old/src/share/classes/java/security/Signature.java	2013-05-14 10:49:13.214766505 +0800
+++ new/src/share/classes/java/security/Signature.java	2013-05-14 10:49:13.094766510 +0800
@@ -248,6 +248,7 @@
         Signature sig;
         if (instance.impl instanceof Signature) {
             sig = (Signature)instance.impl;
+            sig.algorithm = algorithm;
         } else {
             SignatureSpi spi = (SignatureSpi)instance.impl;
             sig = new Delegate(spi, algorithm);