diff --git a/src/css.js b/src/css.js
index 0f1491466..1fbee3f47 100644
--- a/src/css.js
+++ b/src/css.js
@@ -177,7 +177,7 @@ jQuery.each(["height", "width"], function( i, name ) {
 					}
 
 					if ( val != null ) {
-						return val;
+						return val === "" ? "auto" : val;
 					}
 				}
 
@@ -252,7 +252,7 @@ if ( document.defaultView && document.defaultView.getComputedStyle ) {
 			}
 		}
 
-		return ret === "" ? "auto" : ret;
+		return ret;
 	};
 }
 
diff --git a/test/unit/effects.js b/test/unit/effects.js
index 8facb4f54..74b336f1f 100644
--- a/test/unit/effects.js
+++ b/test/unit/effects.js
@@ -6,7 +6,7 @@ test("sanity check", function() {
 });
 
 test("show()", function() {
-	expect(27);
+	expect(28);
 
 	var hiddendiv = jQuery("div.hidden");
 
@@ -14,6 +14,10 @@ test("show()", function() {
 
 	equals( hiddendiv.css("display"), "block", "Make sure a pre-hidden div is visible." );
 
+	var div = jQuery("<div>").hide().appendTo("body").show();
+
+	equal( div.css("display"), "block", "Make sure pre-hidden divs show" );
+
 	QUnit.reset();
 
 	hiddendiv = jQuery("div.hidden");