Validando datas em pt-br com jQuery Validate

assim:

 $.validator.addMethod(  
      "date",  
      function(value, element) {  
           var check = false;  
           var re = /^\d{1,2}\/\d{1,2}\/\d{4}$/;  
           if( re.test(value)){  
                var adata = value.split('/');  
                var gg = parseInt(adata[0],10);  
                var mm = parseInt(adata[1],10);  
                var aaaa = parseInt(adata[2],10);  
                var xdata = new Date(aaaa,mm-1,gg);  
                if ( ( xdata.getFullYear() == aaaa ) && ( xdata.getMonth () == mm - 1 ) && ( xdata.getDate() == gg ) )  
                     check = true;  
                else  
                     check = false;  
           } else  
                check = false;  
           return this.optional(element) || check;  
      },  
      "Insira uma data válida"  
 );