var parts = key.split(".");
                parts[1] = parts[1] ? "." + parts[1] : "";
 
-               if ( value == null ) {
+               if ( value === undefined ) {
                        var data = this.triggerHandler("getData" + parts[1] + "!", [parts[0]]);
                        
-                       if ( data == undefined && this.length )
+                       if ( data === undefined && this.length )
                                data = jQuery.data( this[0], key );
 
-                       return data == null && parts[1] ?
+                       return data === undefined && parts[1] ?
                                this.data( parts[0] ) :
                                data;
                } else
 
 });\r
 \r
 test(".data()", function() {\r
-       expect(16);\r
+       expect(18);\r
        var div = $("#foo");\r
        ok( div.data("test") == undefined, "Check for no data exists" );\r
        div.data("test", "success");\r
        ok( div.data("test") == "success", "Check for added data" );\r
        div.data("test", "overwritten");\r
        ok( div.data("test") == "overwritten", "Check for overwritten data" );\r
-\r
+       div.data("test", undefined);\r
+       ok( div.data("test") == "overwritten", "Check that data wasn't removed");\r
+       div.data("test", null);\r
+       ok( div.data("test") === null, "Check for null data");\r
+       \r
+       div.data("test", "overwritten");\r
        var hits = {test:0}, gets = {test:0};\r
-\r
+       \r
        div\r
                .bind("setData",function(e,key,value){ hits[key] += value; })\r
                .bind("setData.foo",function(e,key,value){ hits[key] += value; })\r