function change_language(from,to){
var toaddstr = '';
var fromaddstr = '';
if (from!=to) {
  str = location.href;
  if (from=='') toaddstr = '/';
  if (to=='') fromaddstr = '/';

  regexp = SITE_URL+from;
  newSubStr = SITE_URL+to;
  if (regexp != str) {
    regexp = regexp+fromaddstr;
    newSubStr = newSubStr+toaddstr
  }
  str = String(str).replace(regexp, newSubStr);
  location.href = str;
}
return false;
}