diff --git a/src/plugins/tool/FindDupes.py b/src/plugins/tool/FindDupes.py
index 47997b206..4cf5501fe 100644
--- a/src/plugins/tool/FindDupes.py
+++ b/src/plugins/tool/FindDupes.py
@@ -109,7 +109,7 @@ class Merge(Tool.Tool,ManagedWindow.ManagedWindow):
         self.use_soundex = 1
 
         base = os.path.dirname(__file__)
-        self.glade_file = "%s/%s" % (base,"merge.glade")
+        self.glade_file = base + os.sep + "merge.glade"
         top = glade.XML(self.glade_file,"dialog","gramps")
 
         # retrieve options