diff --git a/lib/propobj.js b/lib/propobj.js
index 0902b42..c60d431 100644
--- a/lib/propobj.js
+++ b/lib/propobj.js
@@ -26,7 +26,7 @@ var util = require( './util' ),
 
     // whether or not we support defining properties through
     // Object.defineProperty()
-    defprop = ( Object.defineProperty !== undefined ) ? true : false;
+    defprop = !( util.definePropertyFallback() );
 ;