Adds target="_blank" FOR EXTERNAL LINKS on 'a' tags - works on graphical buttons if you made them a tags rather than divs eg.
<script>
$(document).ready(function(){
$.expr[':'].external = function(obj){
return !obj.href.match(/^mailto\:/)
&& (obj.hostname != location.hostname)
&& !obj.href.match(/^javascript\:/)
&& !obj.href.match(/^$/)
};
$('a:external').attr('target', '_blank');
});
</script>