diff --git a/src/jquery/jquery.js b/src/jquery/jquery.js
index 0f79216fe..30396cacc 100644
--- a/src/jquery/jquery.js
+++ b/src/jquery/jquery.js
@@ -1537,7 +1537,7 @@ jQuery.extend({
 			}
 
 			return elem.filter ? 
-				(parseFloat( elem.filter.match(/opacity=([^)]*)/)[1] ) / 100).toString() : 1;
+				(parseFloat( elem.filter.match(/opacity=([^)]*)/)[1] ) / 100).toString() : "1";
 		}
 		
 		// Certain attributes only work when accessed via the old DOM 0 way