function popup(path,width,height,target) {
    if (target=="" || target==undefined) target="_blank";
    if (width=="" || width==undefined) width=500;
    if (height=="" || height==undefined) height=460;
    features = "width="+width+", height="+height+", scrollbars=yes status=yes resizable=no";

		sWidth = 1024;    
		sHeight = 768;
    if(typeof(screen)=='object') {
		 	sWidth = screen.width;
		 	sHeight = screen.height;
		}
		
		xPos = (sWidth-width)/2;
		yPos = (sHeight-height)/2;

    window_handle = window.open(path,target,features);   
    window_handle.moveTo(xPos, yPos);
    window_handle.focus(); 
}