diff --git a/src/network/networkpacket.cpp b/src/network/networkpacket.cpp
index 2867c12a5..c99b987cf 100644
--- a/src/network/networkpacket.cpp
+++ b/src/network/networkpacket.cpp
@@ -552,6 +552,12 @@ NetworkPacket& NetworkPacket::operator<<(video::SColor src)
 
 Buffer<u8> NetworkPacket::oldForgePacket()
 {
+	// this is the dummy packet used to first contact the server
+	if (m_command == 0) {
+		assert(m_datasize == 0);
+		return Buffer<u8>();
+	}
+
 	Buffer<u8> sb(m_datasize + 2);
 	writeU16(&sb[0], m_command);
 	if (m_datasize > 0)
diff --git a/src/unittest/test_connection.cpp b/src/unittest/test_connection.cpp
index ce7464fec..ea280f56b 100644
--- a/src/unittest/test_connection.cpp
+++ b/src/unittest/test_connection.cpp
@@ -277,8 +277,8 @@ void TestConnection::testConnectSendReceive()
 		Simple send-receive test
 	*/
 	{
-		NetworkPacket pkt;
-		pkt.putRawPacket((u8*) "Hello World !", 14, 0);
+		NetworkPacket pkt(0x4b, 0);
+		pkt.putRawString("Hello World !", 14);
 
 		auto sentdata = pkt.oldForgePacket();
 
@@ -306,9 +306,9 @@ void TestConnection::testConnectSendReceive()
 	*/
 	{
 		const int datasize = 30000;
-		NetworkPacket pkt(0, datasize);
+		NetworkPacket pkt(0xff, datasize);
 		for (u16 i=0; i<datasize; i++) {
-			pkt << (u8) i/4;
+			pkt << static_cast<u8>(i/4);
 		}
 
 		infostream << "Sending data (size=" << datasize << "):";