Did you create the variables correctly?
This code is working for me:
var page = 'page.php';
var name = 'pagename';
var width = 200;
var height = 100;
window.open(page,name,'width='+width+', height='+height+',location=yes,menubar=no,resizable=no,toolbar=no,scrollbars=yes');
EDIT
In my webapp I use the following function for opening windows. It should work in all browsers.
function wopen(url, name, w, h, scrollb) {
scrollb = typeof(scrollb) != 'undefined' ? scrollb : 'no';
w += 32;
h += 96;
wleft = (screen.width - w) / 2;
wtop = (screen.height - h) / 2;
var win = window.open(url, name,
'width=' + w + ', height=' + h + ', ' + 'left=' + wleft + ', top=' + wtop + ', ' +
'location=no, menubar=no, ' +
'status=no, toolbar=no, scrollbars=' + scrollb + ', resizable=yes');
// Just in case width and height are ignored
win.resizeTo(w, h);
// Just in case left and top are ignored
win.moveTo(wleft, wtop);
win.focus();
}