focus is not coming event after giving window.focus()

Dear friends,
I am opening a window which loads an applet and after that i am caliing like below.

var win= window.open()
win.focus();
But the focus is not coming on it.

if you have any idea please share it.
Thanks
Rak

Cod eis as below

parentframe.location.href="dummy.html"
var win = window.open("applethtml")
win.focus()

Actually focus is going to parentframe from wheer applet popped out.Eventhough
I am calling " win.focus()" it is not focussong to applet window.

Please share if you guys have any idea on this how we can bvring the focus on window only.