Under windows it shows wrong daylight savings before 2007 on US eastern time -05:00

Windows
"UTC" "Wed Nov 1 12:00:00 2006"
"Local" "Wed Nov 1 08:00:00 2006" <-
"UTC" "Thu Nov 1 12:00:00 2007"
"Local" "Thu Nov 1 08:00:00 2007"

Mac/Linux
"UTC" "Wed Nov 1 12:00:00 2006"
"Local" "Wed Nov 1 07:00:00 2006" <-
"UTC" "Thu Nov 1 12:00:00 2007"
"Local" "Thu Nov 1 08:00:00 2007"

Example:
int main()
{
qDebug()
<< "UTC" << QDateTime( QDate( 2006, 11, 1 ), QTime( 12, 0, 0 ), Qt::UTC ).toString() << endl
<< "Local" << QDateTime( QDate( 2006, 11, 1 ), QTime( 12, 0, 0 ), Qt::UTC ).toLocalTime().toString() << endl
<< "UTC" << QDateTime( QDate( 2007, 11, 1 ), QTime( 12, 0, 0 ), Qt::UTC ).toString() << endl
<< "Local" << QDateTime( QDate( 2007, 11, 1 ), QTime( 12, 0, 0 ), Qt::UTC ).toLocalTime().toString() << endl;
}

If use windows native API from MSDN then it handles correctly daylight savings