...
$("#send").click(function(){
    
    $.ajax({
	     type: 'POST',
	     url: 'process.pl?first=<TMPL_VAR NAME="FR">&last=<TMPL_VAR NAME="LA">',
	     dataType: "json",
	     success: function(data) {

	       if(data){
	         alert("We pass!");
	       }
	     },
	     error: function() {
	       alert("We have a problem!");
	     }
	 });
  });
...