--- a/jdk/src/share/classes/sun/nio/ch/Net.java	Tue Dec 01 08:55:15 2009 -0800
+++ b/jdk/src/share/classes/sun/nio/ch/Net.java	Wed Dec 02 12:17:42 2009 +0000
@@ -68,6 +68,9 @@
         InetSocketAddress isa = (InetSocketAddress)sa;
         if (isa.isUnresolved())
             throw new UnresolvedAddressException(); // ## needs arg
+        InetAddress addr = isa.getAddress();
+        if (!(addr instanceof Inet4Address || addr instanceof Inet6Address))
+            throw new IllegalArgumentException("Invalid address type");
         return isa;
     }