diff --git a/src/test/CMakeLists.txt b/src/test/CMakeLists.txt
index 93bd931..59a247c 100644
--- a/src/test/CMakeLists.txt
+++ b/src/test/CMakeLists.txt
@@ -13,6 +13,7 @@ add_executable(testrunner ${test_SOURCES})
 target_link_libraries(testrunner pieces ${CPPUNIT_LIBRARIES} ${OPENTHREADS_LIBRARIES})
 
 set(tests
+    TestSharedData
     TestAutoPointer
     TestByteArray
     TestByteArraySlicing
diff --git a/src/test/test_smart_pointers.cpp b/src/test/test_smart_pointers.cpp
index a4bcfd5..f0dc6f4 100644
--- a/src/test/test_smart_pointers.cpp
+++ b/src/test/test_smart_pointers.cpp
@@ -1,12 +1,13 @@
 #include <cppunit/TestFixture.h>
 #include <cppunit/extensions/HelperMacros.h>
+#include <Pieces/SharedData>
 #include <Pieces/AutoPointer>
 #include <Pieces/global>
 
 using pcs::AutoPointer;
 
 namespace {
-class MockObject
+class MockObject : public pcs::SharedData
 {
 public:
     static int count;
@@ -25,6 +26,36 @@ class MockObject
 int MockObject::count = 0;
 }
 
+class TestSharedData : public CppUnit::TestFixture
+{
+    CPPUNIT_TEST_SUITE(TestSharedData);
+    CPPUNIT_TEST(testReferenceCount);
+    CPPUNIT_TEST_SUITE_END();
+
+public:
+    void testReferenceCount() {
+        MockObject o;
+        o.ref();
+        CPPUNIT_ASSERT(!o.shared());
+        o.ref();
+        CPPUNIT_ASSERT(o.shared());
+        o.ref();
+        CPPUNIT_ASSERT(o.shared());
+
+        bool v;
+        v = o.deref();
+        CPPUNIT_ASSERT(o.shared());
+        CPPUNIT_ASSERT(v);
+        v = o.deref();
+        CPPUNIT_ASSERT(!o.shared());
+        CPPUNIT_ASSERT(v);
+        v = o.deref();
+        CPPUNIT_ASSERT(!o.shared());
+        CPPUNIT_ASSERT(!v);
+    }
+};
+CPPUNIT_TEST_SUITE_REGISTRATION(TestSharedData);
+
 class TestAutoPointer : public CppUnit::TestFixture
 {
     CPPUNIT_TEST_SUITE(TestAutoPointer);