var opened=false;
function openWin(str,nm,width,height){
    if(width==0){width=700}
    if(height==0){height=500}
	if(opened == false){
		win = open(str,nm,"status=0,scrollbars=1,menubar=0,toolbar=0,location=0,resizeable=0,width="+width+",height="+height);
	}
	else if(opened == true){
		if(win.closed == false)
		win.close(); 
		win = window.open(str,nm,"status=0,scrollbars=1,menubar=0,toolbar=0,location=0,resizeable=0,width="+width+",height="+height);    
	}
	opened = true; 
}