diff --git a/lib/CSSStyleDeclaration.js b/lib/CSSStyleDeclaration.js
index f7cdd42..9c7be05 100644
--- a/lib/CSSStyleDeclaration.js
+++ b/lib/CSSStyleDeclaration.js
@@ -17,7 +17,10 @@ function parseStyles(s) {
   parser.addListener("property", function(e) {
     if (e.invalid) return; // Skip errors
     result[e.property.text] = e.value.text;
-    if (e.important) result.important[e.property.text] = e.important;
+    if (e.important) {
+      result.important = {};
+      result.important[e.property.text] = e.important;
+    }
   });
   s = (''+s).replace(/^;/, '');
   parser.parseStyleAttribute(s);