QNetworkAccessManager::head not working

[jonks]

I have some code like this:

QNetworkAccessManager nam;
QNetworkRequest request(url);
m_reply = nam.head(request);
 
connect(m_reply, SIGNAL(readyRead()), this, SLOT(gotNetworkHeader()));
connect(m_reply, SIGNAL(finished(QNetworkReply*)), this, SLOT(headFinished(QNetworkReply*)));

QNetworkAccessManager nam;
QNetworkRequest request(url);
m_reply = nam.head(request);

connect(m_reply, SIGNAL(readyRead()), this, SLOT(gotNetworkHeader()));
connect(m_reply, SIGNAL(finished(QNetworkReply*)), this, SLOT(headFinished(QNetworkReply*)));

To copy to clipboard, switch view to plain text mode 

readyRead and finished are never signaled.
Does anyone know why?