How to force a screen refresh?

[mkaluza]

I've got the following problem - I'm using a Timer with a callback function to display something with a delay (c.a. 3 secs) using kbooklabel. The problem is, that if I call setValue() from the timer callback func, the contents of the label are changed (no program errors, getValue() returns ok), but the display isn't updated until next button push.
What's more, if I use setValue several times, the "display requests" seem to accumulate, and when I push any button, I can see the label displaying all the values I've assigned to it one after another.

Any working solutions? I've ran out of ideas... :/

Martin