diff --git a/Lib/whichdb.py b/Lib/whichdb.py
index 4dd4e3a..5806118 100644
--- a/Lib/whichdb.py
+++ b/Lib/whichdb.py
@@ -25,6 +25,18 @@
     except IOError:
         pass
 
+    # Check for dumbdbm next -- this has a .dir and and a .dat file
+        f = open(filename + ".dat", "rb")
+        f.close()
+        f = open(filename + ".dir", "rb")
+        try:
+            if f.read(1) in ["'", '"']:
+                return "dumbdbm"
+        finally:
+            f.close()
+    except IOError:
+        pass
+
     # See if the file exists, return None if not
     try:
         f = open(filename, "rb")