--- modules/system/system-behavior.css	Fri May 21 12:19:24 2010
+++ modules/system/system-behavior.css	Fri May 21 12:19:42 2010
@@ -289,17 +289,25 @@
   display: none;
 }
 
-/**
- * Hide elements visually, but keep them available for screen-readers.
- *
- * Used for information required for screen-reader users to understand and use
- * the site where visual display is undesirable. Information provided in this
- * manner should be kept concise, to avoid unnecessary burden on the user. Must
- * not be used for focusable elements (such as links and form elements) as this
- * causes issues for keyboard only or voice recognition users.
- */
-.element-invisible {
-  height: 0;
-  overflow: hidden;
-  position: absolute;
+/**
+ * Hide elements visually, but keep them available for screen-readers.
+ *
+ * Used for information required for screen-reader users to understand and use
+ * the site where visual display is undesirable. Information provided in this
+ * manner should be kept concise, to avoid unnecessary burden on the user. Must
+ * not be used for focusable elements (such as links and form elements) as this
+ * causes issues for keyboard only or voice recognition users. "!important" is 
+ * used to prevent unintentional overrides.
+ */
+.element-invisible {
+  display: block !important;
+  position: absolute !important;
+  left: -999em !important;
+  width: 1px !important;
+  height: 1px !important;
+  overflow: hidden !important;
+  border: none !important;
+  padding: 0 !important;
+  background-color: transparent !important;
+  background-image: none !important;
 }

--- modules/system/system-behavior-rtl.css	Fri May 21 12:18:19 2010
+++ modules/system/system-behavior-rtl.css	Fri May 21 12:20:15 2010
@@ -84,3 +84,10 @@
   float: right;
   margin: 0 0 0 1em;
 }
+
+/**
+ * Hide elements visually, but keep them available for screen-readers.
+ */
+.element-invisible {
+  left: auto !important;
+}