function isspace(c) {
    return (c==' ') || (c=='\t') || (c=='\n') || (c=='\r');
}

function trim(s) {
    while ((s.length > 0) && isspace(s.charAt(0)))
	s = s.substr(1,s.length-1);
    while ((s.length > 0) && isspace(s.charAt(s.length-1)))
	s = s.substr(0,s.length-1);
    return s;
}

function isEmail(s) {
    return (s.length >= 5) && (s.indexOf("@") >= 1) && (s.indexOf(".") >= 0);
}


function openAtCenter(url, name, image_w, image_h) {


var isNN4 = (navigator.appName.indexOf("Netscape") >= 0 && parseInt(navigator.appVersion) == 4 ) ? true : false;

    scr_w = (screen.width  > 0 ? screen.width  : 800)-20;
    scr_h = (screen.height > 0 ? screen.height : 600)-60;
	
    page_w = image_w+64;
	
    if (page_w > scr_w) {
    	page_w = scr_w;
    	hscroll = true;
    }
    else {
	hscroll = false;
    }

    page_h = image_h+96;
  
    if (page_h > scr_h) {
    	page_h = scr_h;
    	vscroll = true;
    }
    else {
	vscroll = false;
    }
    
    var scrollbars = (hscroll || vscroll) ? 'yes' : 'no';
	
	if (!(hscroll || vscroll)){
	    page_w = image_w+48;
	    page_h = image_h+82;
	}
    
    page_x = Math.max(0,(scr_w-page_w)/2);
    page_y = Math.max(0,(scr_h-page_h)/2);

    features = 'left='+page_x+', top='+page_y+', width='+page_w+', height='+page_h+', scrollbars='+scrollbars;
	featuresnn = 'left='+page_x+',top='+page_y+',width='+page_w+',height='+page_h+',scrollbars='+scrollbars;
	
    if(isNN4){
	window.open(url,name,featuresnn);
    }
    else {
	window.open(url,name,features);
    }
    

}