--- a/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java	Wed Dec 18 10:43:11 2013 +0400
+++ b/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java	Fri Jan 10 13:42:44 2014 -0800
@@ -75,7 +75,7 @@
     private PublicKey prevPubKey;
 
     private final static Set<CryptoPrimitive> SIGNATURE_PRIMITIVE_SET =
-                                    EnumSet.of(CryptoPrimitive.SIGNATURE);
+        Collections.unmodifiableSet(EnumSet.of(CryptoPrimitive.SIGNATURE));
 
     private final static DisabledAlgorithmConstraints
         certPathDefaultConstraints = new DisabledAlgorithmConstraints(