maximize button disabled on new window on IE

Hi I have an aplication on vaadin 6.8.4, there is a button that open an URL on a new window, It works fine on firefox and chrome, but on IE Its doing something weird, the maximaze button is disabled, I cant find annything weird, here is my code:

getWindow().open(
new ExternalResource(url),
“_blank”,800,600, Window.BORDER_NONE);

Anyone knows why is this happening? I havent found nothing on the forums.

UPDATE

If I use:

getWindow().open(
new ExternalResource(url),
“_blank”);

It works on IE, but now I can’t set the default size and the border_none.

If someone have the same issue, I solved using getWindow().executeJavascript(javascript);

javascript=“window.open('”+url+“', ‘_blank’, 'fullsize=yes)”