diff --git a/tests/testUtils.cpp b/tests/testUtils.cpp
index 456b8ad6..ee17c923 100644
--- a/tests/testUtils.cpp
+++ b/tests/testUtils.cpp
@@ -51,6 +51,12 @@ bool testSocket::isConnected() const
 }
 
 
+testSocket::size_type testSocket::getBlockSize() const
+{
+	return 16384;
+}
+
+
 void testSocket::receive(vmime::string& buffer)
 {
 	buffer = m_inBuffer;
diff --git a/tests/testUtils.hpp b/tests/testUtils.hpp
index 96daba82..227d1b36 100644
--- a/tests/testUtils.hpp
+++ b/tests/testUtils.hpp
@@ -216,6 +216,8 @@ public:
 	int receiveRaw(char* buffer, const int count);
 	void sendRaw(const char* buffer, const int count);
 
+	size_type getBlockSize() const;
+
 	/** Send data to client.
 	  *
 	  * @buffer data to send