diff --git a/alethzero/MainWin.cpp b/alethzero/MainWin.cpp
index c4268e9b1..2d7146426 100644
--- a/alethzero/MainWin.cpp
+++ b/alethzero/MainWin.cpp
@@ -726,7 +726,7 @@ void Main::readSettings(bool _skipGeometry)
 	ui->enableOptimizer->setChecked(m_enableOptimizer);
 	ui->clientName->setText(s.value("clientName", "").toString());
 	if (ui->clientName->text().isEmpty())
-		ui->clientName->setText(QInputDialog::getText(this, "Enter identity", "Enter a name that will identify you on the peer network"));
+		ui->clientName->setText(QInputDialog::getText(nullptr, "Enter identity", "Enter a name that will identify you on the peer network"));
 	ui->idealPeers->setValue(s.value("idealPeers", ui->idealPeers->value()).toInt());
 	ui->port->setValue(s.value("port", ui->port->value()).toInt());
 	ui->nameReg->setText(s.value("nameReg", "").toString());
diff --git a/libethcore/CommonEth.cpp b/libethcore/CommonEth.cpp
index c70bc353b..8de20c21d 100644
--- a/libethcore/CommonEth.cpp
+++ b/libethcore/CommonEth.cpp
@@ -32,7 +32,7 @@ namespace dev
 namespace eth
 {
 
-const unsigned c_protocolVersion = 51;
+const unsigned c_protocolVersion = 52;
 const unsigned c_databaseVersion = 5;
 
 static const vector<pair<u256, string>> g_units =