>This probably not any help, but that behavior is more prevalent when the clicking is "rapid".
>

Thanks, Sam. I assume from your reply, that you've seen it too. I'm not clicking really quickly, I just want to change order and see the sorting arrows. On the 5th or 6th click I do not see the change.

But may be I need to introduce some check to see, if the previous click was really processed... I need to think on this idea.