Opening sized popups with Flash/Javascript

I know this is an easy one, but I can’t figure it out. I’m trying to open two sized popup windows from a Flash file, using this code in the main timeline:

_root.openWinCentre = function (url, winName, w, h, toolbar, location, directories, status, menubar, scrollbars, resizable) {
getURL (“javascript:var myWin; if(!myWin || myWin.closed){myWin = window.open(’” + url + “’,’” + winName + “’,’” + “width=” + w + “,height=” + h + “,toolbar=” + toolbar + “,location=” + location + “,directories=” + directories + “,status=” + status + “,menubar=” + menubar + “,scrollbars=” + scrollbars + “,resizable=” + resizable + “,top=’+((screen.height/2)-(” + h/2 + “))+’,left=’+((screen.width/2)-(” + w/2 + “))+’” + “’)}else{myWin.focus();};void(0);”);
}

and this code in the individual buttons (windowName is given a value in the level above the button, which I’ve traced and is coming through):

on (release) {
address = linkname;
target_winName = windowName;
width = 800;
height = 700;
toolbar = 0;
location = 0;
directories = 0;
status = 0;
menubar = 0;
scrollbars = 1;
resizable = 0;

//sends data back to the function 
_root.openWinCentre(address, target_winName, width, height, toolbar, location, directories, status, menubar, scrollbars, resizable);

}

The problem: once a window is opened, the other cannot be opened from the Flash file without first closing the opened popup.

Does anyone have an idea on what the issue is? Or a better/different code for popups?

Help is appreciated - thanks,

Steve