[support] konqueror and unable to login D5/D6

Recently there has been a qt4-webkit upgrade in sid and I'm not able anymore to login into D5/D6. Everything is fine with a 4.X. In D6 I get redirected to en/node. D5 redirection was customised so it may not be of any help (user/0). If I reach the login page and delete the cookies, I'm able to login. Other browsers works fine (Opera, IE6/7, ffox, Chrome). Stil I am able to login with konqueror in other sites.

Maybe the issue is caused by previous session invalidation.

Did anyone experienced the same problem?

Is it a legit and more strict management of cookies by konqueror and other browsers may follow, a bug in konqueror or a bug in drupal?