QTcpServer Error Setting proxy

[CuteKQ]

Hi all, Im trying to set proxy for a QTcpSopcket, but suddenly when I call connectToHost()
I face with this error :" QAbstractSocket::UnsupportedSocketOperationError , The requested socket operation is not supported by the local operating system (e.g., lack of IPv6 support). "

where is the problem?

here the code :

@ m_tcpSocket = new QTcpSocket();

connect(m_tcpSocket,SIGNAL(connected()),this,SLOT(sltConnected()));
connect(m_tcpSocket,SIGNAL(stateChanged(QAbstractSocket::SocketState)),
        this,SLOT(sltStateChanged(QAbstractSocket::SocketState)));
connect(m_tcpSocket,SIGNAL(error(QAbstractSocket::SocketError)),
        this,SLOT(sltError(QAbstractSocket::SocketError)));

p.setHostName("118.97.63.227");
p.setPort(8080);
p.setType(QNetworkProxy::HttpProxy);

m_tcpSocket->setProxy(p);
m_tcpSocket->connectToHost("www.google.com",80);@