We removed deleteExpando after 1.4.2, for some reason. This caused problems with removeData() (no arguments). Fixes #7209.

src/support.js

@@ -61,6 +61,7 @@
 		optSelected: opt.selected,
 
 		// Will be defined later
+		deleteExpando: true,
 		optDisabled: false,
 		checkClone: false,
 		scriptEval: false,
@@ -91,6 +92,15 @@
 		delete window[ id ];
 	}
 
+	// Test to see if it's possible to delete an expando from an element
+	// Fails in Internet Explorer
+	try {
+		delete script.test;
+
+	} catch(e) {
+		jQuery.support.deleteExpando = false;
+	}
+
 	root.removeChild( script );
 
 	if ( div.attachEvent && div.fireEvent ) {

test/unit/data.js

@@ -284,11 +284,16 @@ test(".data(Object)", function() {
 });
 
 test("jQuery.removeData", function() {
-	expect(5);
+	expect(7);
 	var div = jQuery("#foo")[0];
 	jQuery.data(div, "test", "testing");
 	jQuery.removeData(div, "test");
 	equals( jQuery.data(div, "test"), undefined, "Check removal of data" );
+
+	jQuery.data(div, "test2", "testing");
+	jQuery.removeData( div );
+	ok( !jQuery.data(div, "test2"), "Make sure that the data property no longer exists." );
+	ok( !div[ jQuery.expando ], "Make sure the expando no longer exists, as well." );
 	
 	var obj = {};
 	jQuery.data(obj, "test", "testing");