Since I upgraded to KDE SC 4.9.3 (was on 4.9.2 before) some keys of my password are lost. There is some pattern in it:

-it will only happen on the first login, i.e. when authentication failed the next login will work
-it has never been the first character, but usually are characters 2, 3, and sometimes 4
-it does not depend on the character, it happens the same if I just press one key over and over again
-once I'm beyond the point of loss (i.e. the characters are accepted again as I'm at character 5) I can erase the password line and type the whole password in without problems
-it does not depend on the selected user

Reproducible: Always