diff --git a/ndn-cpp/name.cpp b/ndn-cpp/name.cpp
index 1496219..22102bb 100644
--- a/ndn-cpp/name.cpp
+++ b/ndn-cpp/name.cpp
@@ -9,6 +9,7 @@
 #include "name.hpp"
 
 using namespace std;
+using namespace ndn::ptr_lib;
 
 namespace ndn {
 
@@ -131,7 +132,7 @@
 Blob 
 Name::Component::makeSegment(unsigned long segment)
 {
-  ptr_lib::shared_ptr<vector<unsigned char> > value;
+  shared_ptr<vector<unsigned char> > value;
   
   // Add the leading zero.
   value->push_back(0);
diff --git a/ndn-cpp/security/key-chain.cpp b/ndn-cpp/security/key-chain.cpp
index b280c41..6a7d502 100644
--- a/ndn-cpp/security/key-chain.cpp
+++ b/ndn-cpp/security/key-chain.cpp
@@ -12,6 +12,7 @@
 #include "key-chain.hpp"
 
 using namespace std;
+using namespace ndn::ptr_lib;
 
 namespace ndn {
 
@@ -115,7 +116,7 @@
 }
 
 void
-KeyChain::verifyData(const ptr_lib::shared_ptr<Data>& data, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed)
+KeyChain::verifyData(const shared_ptr<Data>& data, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed)
 {
 #if 0
   _LOG_TRACE("Enter Verify");
diff --git a/ndn-cpp/sha256-with-rsa-signature.cpp b/ndn-cpp/sha256-with-rsa-signature.cpp
index aad9c9f..c2c933f 100644
--- a/ndn-cpp/sha256-with-rsa-signature.cpp
+++ b/ndn-cpp/sha256-with-rsa-signature.cpp
@@ -7,13 +7,14 @@
 #include "sha256-with-rsa-signature.hpp"
 
 using namespace std;
+using namespace ndn::ptr_lib;
 
 namespace ndn {
 
-ptr_lib::shared_ptr<Signature> 
+shared_ptr<Signature> 
 Sha256WithRsaSignature::clone() const
 {
-  return ptr_lib::shared_ptr<Signature>(new Sha256WithRsaSignature(*this));
+  return shared_ptr<Signature>(new Sha256WithRsaSignature(*this));
 }
 
 void