diff --git a/perl/t/06_stream_unpack2.t b/perl/t/06_stream_unpack2.t
index 78ca8f7c..bb6fe93d 100644
--- a/perl/t/06_stream_unpack2.t
+++ b/perl/t/06_stream_unpack2.t
@@ -2,8 +2,16 @@ use strict;
 use warnings;
 use Data::MessagePack;
 use Test::More tests => 9;
+use t::Util;
+
+my $input = [
+    false,true,null,0,0,0,0,0,0,0,0,0,-1,-1,-1,-1,-1,
+    127,127,255,65535,4294967295,-32,-32,-128,-32768,
+    -2147483648,0.0,-0.0,1.0,-1.0,"a","a","a","","","",
+    [0],[0],[0],[],[],[],{},{},{},
+    {"a" => 97},{"a" => 97},{"a" => 97},[[]],[["a"]]
+];
 
-my $input = [ 42, "foo", { x => [ (1) x 16 ] }, undef, 1 ];
 my $packed = Data::MessagePack->pack($input);
 is_deeply(Data::MessagePack->unpack($packed), $input);
 
@@ -16,30 +24,20 @@ is_deeply(Data::MessagePack->unpack($packed), $input);
 
 {
     my $up = Data::MessagePack::Unpacker->new();
-    is $up->execute(substr($packed, 0, 3), 0), 3;
-    ok !$up->is_finished;
-    $up->execute($packed, 3);
-    ok $up->is_finished;
-    is_deeply $up->data, $input;
-}
+    $packed x= 3;
 
+    my $offset = 0;
+    for my $i(1 .. 3) {
+        note "block $i (offset: $offset/".length($packed).")";
+        note "starting 3 bytes: ", join " ", map { unpack 'H2', $_ }
+            split //, substr($packed, $offset, 3);
 
-{
-    my $up = Data::MessagePack::Unpacker->new();
-    my $size = 8;
-
-    note "packed size: ", length($packed);
-    open my $stream, '<:bytes :scalar', \$packed;
-    binmode $stream;
-    my $buff;
-    while( read($stream, $buff, $size) ) {
-        note "buff: ", join " ", map { unpack 'H2', $_ } split //, $buff;
-
-        $up->execute($buff);
+        $offset = $up->execute($packed, $offset);
+        ok $up->is_finished, 'finished';
+        my $data = $up->data;
+        is_deeply $data, $input;
+        $up->reset();
     }
-    ok $up->is_finished, 'is_finished';
-    my $data = $up->data;
-    note explain($data);
-    is_deeply $data, $input;
 }
 
+
diff --git a/perl/t/09_stddata.t b/perl/t/09_stddata.t
index b6a612eb..976fc5d3 100644
--- a/perl/t/09_stddata.t
+++ b/perl/t/09_stddata.t
@@ -28,7 +28,7 @@ for my $mpac($mpac1, $mpac2) {
     my $offset = 0;
     my $i = 0;
     while($offset < length($mpac)) {
-        $offset += $mps->execute($mpac, $offset);
+        $offset = $mps->execute($mpac, $offset);
         is_deeply $mps->data, $data[$i], "data[$i]";
         $mps->reset;
         $i++;
diff --git a/perl/t/10_splitted_bytes.t b/perl/t/10_splitted_bytes.t
new file mode 100755
index 00000000..232d8707
--- /dev/null
+++ b/perl/t/10_splitted_bytes.t
@@ -0,0 +1,40 @@
+#!perl
+
+# This feature is not yet supported, but 0.23 (or former) caused SEGV in this code,
+# so we put it here.
+
+use strict;
+use warnings;
+use Data::MessagePack;
+use Test::More;
+use t::Util;
+
+my $input = [
+    false,true,null,0,0,0,0,0,0,0,0,0,-1,-1,-1,-1,-1,
+    127,127,255,65535,4294967295,-32,-32,-128,-32768,
+    -2147483648,0.0,-0.0,1.0,-1.0,"a","a","a","","","",
+    [0],[0],[0],[],[],[],{},{},{},
+    {"a" => 97},{"a" => 97},{"a" => 97},[[]],[["a"]]
+];
+
+my $packed = Data::MessagePack->pack($input);
+
+foreach my $size(1 .. 16) {
+    local $TODO = "Splitted byte streaming is not yet supported (bufer size: $size)";
+
+    my $up = Data::MessagePack::Unpacker->new();
+
+    open my $stream, '<:bytes :scalar', \$packed;
+    binmode $stream;
+    my $buff;
+    while( read($stream, $buff, $size) ) {
+        #note "buff: ", join " ", map { unpack 'H2', $_ } split //, $buff;
+
+        $up->execute($buff);
+    }
+    ok $up->is_finished, 'is_finished';
+    my $data = $up->data;
+    is_deeply $data, $input;
+}
+
+done_testing;
diff --git a/perl/t/Util.pm b/perl/t/Util.pm
index c8debefb..ad69c4d5 100644
--- a/perl/t/Util.pm
+++ b/perl/t/Util.pm
@@ -1,6 +1,7 @@
 package t::Util;
 use strict;
 use warnings;
+use Data::MessagePack;
 
 sub import {
     my $pkg = caller(0);
@@ -15,6 +16,7 @@ sub import {
     *{"$pkg\::false"} = sub () {
         Data::MessagePack::false()
     };
+    *{"$pkg\::null"} = sub() { undef };
 }
 
 1;