diff --git a/ChangeLog b/ChangeLog
index bd80d818be..e831ade0c5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Mon May  7 20:23:29 2012  Tanaka Akira  <akr@fsij.org>
+
+	* lib/securerandom.rb (random_bytes): call to_int method for the
+	  argument at first.
+
+Mon May  7 20:23:29 2012  Tanaka Akira  <akr@fsij.org>
+
+	* lib/securerandom.rb: show actual read length in an error message.
+
 Mon May  7 11:09:20 2012  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/bigdecimal/bigdecimal.c (Init_bigdecimal): define IDs before
diff --git a/lib/securerandom.rb b/lib/securerandom.rb
index 04e8bc205e..d4ab947f54 100644
--- a/lib/securerandom.rb
+++ b/lib/securerandom.rb
@@ -54,7 +54,7 @@ module SecureRandom
   # If secure random number generator is not available,
   # NotImplementedError is raised.
   def self.random_bytes(n=nil)
-    n ||= 16
+    n = n ? n.to_int : 16
 
     if defined? OpenSSL::Random
       @pid = 0 if !defined?(@pid)
@@ -80,7 +80,7 @@ module SecureRandom
           @has_urandom = true
           ret = f.readpartial(n)
           if ret.length != n
-            raise NotImplementedError, "Unexpected partial read from random device"
+            raise NotImplementedError, "Unexpected partial read from random device: only #{ret.length} for #{n} bytes"
           end
           return ret
         }
diff --git a/version.h b/version.h
index b34fca3c97..dcefb796cf 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.3"
-#define RUBY_PATCHLEVEL 205
+#define RUBY_PATCHLEVEL 206
 
 #define RUBY_RELEASE_DATE "2012-05-07"
 #define RUBY_RELEASE_YEAR 2012