QIntValidator blocks negative numbers in Swedish locale

Setting a QIntValidator on a QLineEdit fails to accept negative values entered when the locale is sv_SE. The following code should allow numbers from -9 to 9 in the LineEdit, but Qt blocks the minus sign when the locale is Swedish.

QLineEdit* leSE = new QLineEdit();
QLocale locSE("sv_SE");
QIntValidator* pValidator = new QIntValidator(-9, 9, leSE);
pValidator->setLocale(locSE);
leSE->setValidator(pValidator);

This same method works well in many other locales, including similar Scandinavian languages such an Finnish.