Qt application+hide taskbar

Recently I wrote simple reminder app. I want it to behave like desktop widget. But I don't know what to do to hide it from taskbar.
I tried a lot of window flags. When I set it to Qt::Tool it seems to work fine, but when I invoke child window (configuration window) and then close it, main window close as well.
So my question is is there any other ways to hide taskbar button?
At least it can be unix-only function :-)

Try accepted answer from here [stackoverflow.com].