Providing own cell header mouseover/mouseout event methods per column

How can I set my own method for the mouseover event for a specific column header?

I tried for all header the following:

obj.getTemplate("top/item").setEvent("onMouseOver", mymethod());

but this only invokes mymethod during writing the grid. But anyway, that is not what I really want to achieve, but I am already having problems here.

Basically I would like to declare for each column header for mouseover and mouseout a specific behavior, but I have a hard time figuring it out.

Thankfull for any help or hints...

You can try with this workaround (last updatet Nov-17).
(never try the onmouseover in it, but I think there is no diference)
http://activewidgets.com/javascript.forum.2094.5/context-menu-on-header.html