Fix pattern validator failing on optional fields if pattern doesn't allow empty value (Fix jquerytools#605)

Author: Olivier Poitrey

src/validator/validator.js

@@ -251,9 +251,8 @@
 		return !!v; 			
 	});
 
-	v.fn("[pattern]", function(el) {
-		var p = new RegExp("^" + el.attr("pattern") + "$");  
-		return p.test(el.val()); 			
+	v.fn("[pattern]", function(el, v) {
+		return v === '' || new RegExp("^" + el.attr("pattern") + "$").test(v);
 	});