QLineEdit password bug when using hardware keyboard

When you use the qwerty keyboard to type characters into a password field (QLineEdit, QLineEdit::Password) a char overwrites another character.
This is 100% reproducable.

Steps to reproduce:
type in a character
wait at least until the character is replaced by a dot
type another char

expected result:
two characters displayed

actual result
the last char is overwritten by the previously typed character

This defect does not occur when you type using the onscreen keyboard nor when you type very quickly using the qwerty keyboard.