LinuxQuestions.org - weird kde4 menu shortcut key behavior

I'm running kde4 (4.1.2) on slackware-current. There is something rather strange that happens since 4.1.0 (haven't tested earlier versions), and I believe this is the one showstopper that keeps me from using kde4 more.

This is what I do:

Code:

telinit 3

rm -r /home/jan/.kde

telinit 4

login as user jan
<alt><F1> opens the K menu
logout
login
<alt><F1> opens the K menu
change language to dutch
<alt><F1> opens the K menu
logout
login
<alt><F1> no longer opens the K menu

Has anyone had the same problem?
Where could I start looking for a problem?