function swapLang(lang) {
    lang = '/' + lang + '/';
    currentLang = '';
    s = new String(location.href);

    if (s.indexOf('\/b5\/') > 0) {
        currentLang = 'b5';
        s = s.replace(/\/b5\//g, lang);
    }
    if (s.indexOf('\/en\/') > 0) {
        currentLang = 'en';
        s = s.replace(/\/en\//g, lang);
    }
    
    
    location.href = s;
    
}