diff --git a/tests/unit/effects/effects.html b/tests/unit/effects/effects.html
index 7ddacf7bb..4538ecb03 100644
--- a/tests/unit/effects/effects.html
+++ b/tests/unit/effects/effects.html
@@ -96,6 +96,8 @@
 <h2 id="qunit-userAgent"></h2>
 <ol id="qunit-tests"></ol>
 <div id="qunit-fixture">
+<div id="elem" class="test">
+</div>
 <div class="hidden test">
 	<div>.</div>
 </div>
diff --git a/tests/unit/effects/effects_core.js b/tests/unit/effects/effects_core.js
index 928d4c15b..11e9d0b45 100644
--- a/tests/unit/effects/effects_core.js
+++ b/tests/unit/effects/effects_core.js
@@ -16,6 +16,24 @@ var minDuration = 15,
 
 module( "effects.core" );
 
+// TODO: test all signatures of .show(), .hide(), .toggle().
+// Look at core's signatures and UI's signatures.
+asyncTest( ".hide() with step", function() {
+	expect( 1 );
+	var element = $( "#elem" ),
+		step = function() {
+			ok( true, "step callback invoked" );
+			step = $.noop;
+		};
+
+	element.hide({
+		step: function() {
+			step();
+		},
+		complete: start
+	});
+});
+
 test( "Immediate Return Conditions", function() {
 	var hidden = $( "div.hidden" ),
 		count = 0;
diff --git a/ui/jquery.ui.effect.js b/ui/jquery.ui.effect.js
index 41aeb4819..f3d9929b0 100644
--- a/ui/jquery.ui.effect.js
+++ b/ui/jquery.ui.effect.js
@@ -1106,14 +1106,29 @@ function _normalizeArguments( effect, options, speed, callback ) {
 	return effect;
 }
 
-function standardSpeed( speed ) {
-	// valid standard speeds
-	if ( !speed || typeof speed === "number" || $.fx.speeds[ speed ] ) {
+function standardAnimationOption( option ) {
+	// Valid standard speeds (nothing, number, named speed)
+	if ( !option || typeof option === "number" || $.fx.speeds[ option ] ) {
 		return true;
 	}
 
-	// invalid strings - treat as "normal" speed
-	return typeof speed === "string" && !$.effects.effect[ speed ];
+	// Invalid strings - treat as "normal" speed
+	if ( typeof option === "string" && !$.effects.effect[ option ] ) {
+		return true;
+	}
+
+	// Complete callback
+	if ( $.isFunction( option ) ) {
+		return true;
+	}
+
+	// Options hash (but not naming an effect)
+	if ( typeof option === "object" && !option.effect ) {
+		return true;
+	}
+
+	// Didn't match any standard API
+	return false;
 }
 
 $.fn.extend({
@@ -1163,39 +1178,41 @@ $.fn.extend({
 		return queue === false ? this.each( run ) : this.queue( queue || "fx", run );
 	},
 
-	_show: $.fn.show,
-	show: function( speed ) {
-		if ( standardSpeed( speed ) ) {
-			return this._show.apply( this, arguments );
-		} else {
-			var args = _normalizeArguments.apply( this, arguments );
-			args.mode = "show";
-			return this.effect.call( this, args );
-		}
-	},
+	show: (function( orig ) {
+		return function( option ) {
+			if ( standardAnimationOption( option ) ) {
+				return orig.apply( this, arguments );
+			} else {
+				var args = _normalizeArguments.apply( this, arguments );
+				args.mode = "show";
+				return this.effect.call( this, args );
+			}
+		};
+	})( $.fn.show ),
 
-	_hide: $.fn.hide,
-	hide: function( speed ) {
-		if ( standardSpeed( speed ) ) {
-			return this._hide.apply( this, arguments );
-		} else {
-			var args = _normalizeArguments.apply( this, arguments );
-			args.mode = "hide";
-			return this.effect.call( this, args );
-		}
-	},
+	hide: (function( orig ) {
+		return function( option ) {
+			if ( standardAnimationOption( option ) ) {
+				return orig.apply( this, arguments );
+			} else {
+				var args = _normalizeArguments.apply( this, arguments );
+				args.mode = "hide";
+				return this.effect.call( this, args );
+			}
+		};
+	})( $.fn.hide ),
 
-	// jQuery core overloads toggle and creates _toggle
-	__toggle: $.fn.toggle,
-	toggle: function( speed ) {
-		if ( standardSpeed( speed ) || typeof speed === "boolean" || $.isFunction( speed ) ) {
-			return this.__toggle.apply( this, arguments );
-		} else {
-			var args = _normalizeArguments.apply( this, arguments );
-			args.mode = "toggle";
-			return this.effect.call( this, args );
-		}
-	},
+	toggle: (function( orig ) {
+		return function( option ) {
+			if ( standardAnimationOption( option ) || typeof option === "boolean" ) {
+				return orig.apply( this, arguments );
+			} else {
+				var args = _normalizeArguments.apply( this, arguments );
+				args.mode = "toggle";
+				return this.effect.call( this, args );
+			}
+		};
+	})( $.fn.toggle ),
 
 	// helper functions
 	cssUnit: function(key) {