QPushButton, QTabOrder and return key

[jcr]

Hello,
I have created two buttons:

cancelButton = new QPushButton("Cancel");
  layout->addWidget(cancelButton, 2, 0);
  submitButton = new QPushButton("Submit");
  layout->addWidget(submitButton, 2, 1);

cancelButton = new QPushButton("Cancel");
  layout->addWidget(cancelButton, 2, 0);
  submitButton = new QPushButton("Submit");
  layout->addWidget(submitButton, 2, 1);

To copy to clipboard, switch view to plain text mode 

and connected them like this

connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));
  connect(submitButton, SIGNAL(clicked()), this, SLOT(checkLogin()));

connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));
  connect(submitButton, SIGNAL(clicked()), this, SLOT(checkLogin()));

To copy to clipboard, switch view to plain text mode 

then, I specified some tabordering

setTabOrder(usernameLine, passwordLine);
  setTabOrder(passwordLine, submitButton);
  setTabOrder(submitButton, cancelButton);

setTabOrder(usernameLine, passwordLine);
  setTabOrder(passwordLine, submitButton);
  setTabOrder(submitButton, cancelButton);

To copy to clipboard, switch view to plain text mode 

once the password is entered and I press tab, the submitButton is highlighted but pressing the return key on my mac does not trigger anything. If I click the button with the mouse, it works fine. I am using Qt 4.2.0-rc1.
Thanks for any help