diff --git a/tests/unit/tabs/tabs_methods.js b/tests/unit/tabs/tabs_methods.js
index 7c72cd26dd8..bd28316c5f4 100644
--- a/tests/unit/tabs/tabs_methods.js
+++ b/tests/unit/tabs/tabs_methods.js
@@ -18,7 +18,7 @@ test('destroy', function() {
 });
 
 test('enable', function() {
-    expect(8);
+    expect(12);
 
 	el = $('#tabs1').tabs({ disabled: [ 0, 1 ] });
 	el.tabs("enable", 1);
@@ -31,6 +31,18 @@ test('enable', function() {
 	ok( !$('li.ui-state-disabled', el).length, 'enable all');
 	same(el.tabs('option', 'disabled'), false, 'update property');
 
+	// enable one tab
+	el.tabs({ disabled: true });
+	el.tabs("enable", 1);
+	ok( $('li:eq(1)', el).is(':not(.ui-state-disabled)'), 'remove class from li');
+	same(el.tabs('option', 'disabled'), [ 0, 2 ], 'update property');
+
+	// all tabs already enabled
+	el.tabs({ disabled: false });
+	el.tabs("enable", 1);
+	ok( !$('li.ui-state-disabled', el).length, 'enable all');
+	same(el.tabs('option', 'disabled'), false, 'update property');
+
 	el.tabs('destroy');
 	// enable all tabs one by one
 	el.tabs({ disabled: [ 1, 2 ] });
@@ -43,7 +55,7 @@ test('enable', function() {
 });
 
 test('disable', function() {
-    expect(12);
+    expect(14);
 
 	// normal
 	el = $('#tabs1').tabs();
@@ -61,6 +73,12 @@ test('disable', function() {
 	same( $('li.ui-state-disabled', el).length, 3, 'disable all');
 	same(el.tabs('option', 'disabled'), true, 'set to true');
 
+	// all tabs already disabled
+	el.tabs({ disabled: true });
+	el.tabs("disable", 1);
+	ok( $('li.ui-state-disabled', el).length, 'disable all');
+	same(el.tabs('option', 'disabled'), true, 'set to true');
+
 	el.tabs("destroy");
 	// disable all tabs one by one
 	el.tabs();
diff --git a/ui/jquery.ui.tabs.js b/ui/jquery.ui.tabs.js
index f73799f02c3..5c525b34a99 100755
--- a/ui/jquery.ui.tabs.js
+++ b/ui/jquery.ui.tabs.js
@@ -513,6 +513,9 @@ $.widget( "ui.tabs", {
 
 	enable: function( index ) {
 		var disabled = this.options.disabled;
+		if ( disabled === false ) {
+			return;
+		}
 
 		if ( index === undefined ) {
 			disabled = false;
@@ -523,7 +526,9 @@ $.widget( "ui.tabs", {
 					return num !== index ? num : null;
 				});
 			} else {
-				disabled = [ index ];
+				disabled = $.map( this.lis, function( li, num ) {
+					return num !== index ? num : null;
+				});
 			}
 		}
 		this._setupDisabled( disabled );
@@ -531,6 +536,9 @@ $.widget( "ui.tabs", {
 
 	disable: function( index ) {
 		var disabled = this.options.disabled;
+		if ( disabled === true ) {
+			return;
+		}
 
 		if ( index === undefined ) {
 			disabled = true;