diff --git a/gst/gobject2gtk.c b/gst/gobject2gtk.c
index a539d401ce..c53aa366ad 100644
--- a/gst/gobject2gtk.c
+++ b/gst/gobject2gtk.c
@@ -109,16 +109,16 @@ g2g_object_class_find_property(GObjectClass *class, const gchar *name)
 
   //fprintf(stderr,"class name is %s\n",gtk_type_name(class->type));
 
-  gtk_object_arg_get_info(class->type,name,&info);
+  // the return value NULL if no error
+  if (gtk_object_arg_get_info(class->type,name,&info) != NULL) {
+    return NULL;
+  }
+  
   spec = g_new0(GParamSpec,1);
 
-  if (info) {
-    spec->name = (gchar *) name;
-    spec->value_type = info->type;
-    spec->flags = info->arg_flags;
-  } else {
-    spec->value_type = GTK_TYPE_NONE;
-  }
+  spec->name = (gchar *) name;
+  spec->value_type = info->type;
+  spec->flags = info->arg_flags;
 
   return spec;
 }