if the setting's unique be true,tag should be case sensitive.

README.md

@@ -11,6 +11,8 @@ list of tags!
 
 [View Demo](http://xoxco.com/projects/code/tagsinput/)
 
+[Test it yourself using this jsFiddle Demo](http://jsfiddle.net/7aDak/)
+
 Created by [XOXCO](http://xoxco.com)
 
 

jquery.tagsinput.js

@@ -163,10 +163,11 @@
 	
 	$.fn.tagExist = function(val) {
 		var id = $(this).attr('id');
-		var tagslist = $(this).val().split(delimiter[id]);
+		val = val.toLowerCase();
+		var tagslist = $(this).val().toLowerCase().split(delimiter[id]);
 		return (jQuery.inArray(val, tagslist) >= 0); //true when tag exists, false when not
 	};
-	
+
 	// clear all existing tags and import new ones from a string
 	$.fn.importTags = function(str) {
                 id = $(this).attr('id');