diff --git a/perl/Changes b/perl/Changes
index b03a9d0..f32d5f4 100644
--- a/perl/Changes
+++ b/perl/Changes
@@ -1,3 +1,7 @@
+0.13
+
+    - clearly specify requires_c99(), because msgpack C header requires C99.
+
 0.12
 
     - PERL_NO_GET_CONTEXT makes horrible dTHXs. remove it.
diff --git a/perl/lib/Data/MessagePack.pm b/perl/lib/Data/MessagePack.pm
index dcc713d..ee07d35 100644
--- a/perl/lib/Data/MessagePack.pm
+++ b/perl/lib/Data/MessagePack.pm
@@ -4,7 +4,7 @@ use warnings;
 use XSLoader;
 use 5.008001;
 
-our $VERSION = '0.12';
+our $VERSION = '0.13';
 our $PreferInteger = 0;
 
 our $true  = do { bless \(my $dummy = 1), "Data::MessagePack::Boolean" };