function externalLinks()
{

var thispagedomain = ExtractDomainName(document.URL);
for(var i = 0; i <= document.links.length - 1; i++) {
   var url = document.links[i].href.toLowerCase();
   if(url.indexOf('http://') != 0) { continue; }
   var hrefdomain = ExtractDomainName(url);
   if(thispagedomain != hrefdomain) { 
      document.links[i].target = '_blank';
      }
   }
}

function ExtractDomainName(s) {
var i = s.indexOf('//');
if(i > -1) { s = s.substr(i+2); }
i = s.indexOf('/');
if(i > -1) { s = s.substr(0,i); }
i = s.indexOf(':');
if(i > -1) { s = s.substr(0,i); }
var re = /[a-z]/i;
if(! re.test(s)) { return s; }
var a = s.split('.');
if(a.length < 2) { return s; }
var domain = a[a.length-2] + '.' + a[a.length-1];
if(a.length > 2) {
   if(a[a.length-2].length==2 && a[a.length-1].length==2) {
      domain = a[a.length-3] + '.' + domain;
      }
   }
return domain.toLowerCase();
}


window.onload = externalLinks;