function Is() {
	agent  = navigator.userAgent.toLowerCase();
	this.major = parseInt(navigator.appVersion);
	this.minor = parseFloat(navigator.appVersion);
	this.ns = ((agent.indexOf('mozilla') != -1) && 
	(agent.indexOf('spoofer') == -1) && (agent.indexOf('compatible') == -1) &&
	(agent.indexOf('opera') == -1) &&
	(agent.indexOf('webtv') == -1));	
	this.ns2   = (this.ns && (this.major      ==    3));
	this.ns3   = (this.ns && (this.major      ==    3));
	this.ns4   = (this.ns && (this.major      ==    4));
	this.ns6   = (this.ns && (this.major      >=    5));
	this.ie    = (agent.indexOf("msie")       !=   -1);
	this.ie3   = (this.ie && (this.major      < 4));
	this.ie4   = (this.ie && (this.major      ==    4) && (agent.indexOf("msie 5.0")   ==   -1));
	this.ie5   = (this.ie && (this.major      ==    4) && (agent.indexOf("msie 5.0")   !=   -1));
	this.ieX = (this.ie && !this.ie3 && !this.ie4); 
}
var is = new Is();
function openWin(mypage,myname,w,h,features) {
	if(is.ns4 ||is.ns6) {
		available_width=innerWidth;
		available_height=innerHeight;
	}else if(is.ie4 || is.ie5) {
		available_width=document.body.clientWidth;
		available_height=document.body.clientHeight;
	}
var winl = (available_width-w)/2;
var wint = (available_height-h)/2
if (winl < 0) winl = 0;
if (wint < 0) wint = 0;
var settings = 'height=' + h + ',';
settings += 'width=' + w + ',';
settings += 'top=' + wint + ',';
settings += 'left=' + winl + ',';
settings += 'directories=no,';
settings += 'directories=0,';
settings += 'status=no,';
settings += 'status=0,';
settings += 'resizable=no,';
settings += 'resizable=0,';
if(myname = 'voorwaarden'){
	settings += 'scrollbars=yes,';
	settings += 'scrollbars=1,';
}else{
	settings += 'scrollbars=no,';
	settings += 'scrollbars=0,';
}
settings += 'toolbar=no,';
settings += 'toolbar=0,';
settings += 'menubar=no,';
settings += 'menubar=0,';
settings += features;
win = window.open(mypage,myname,settings);
win.window.focus();
}