diff --git a/hgext/transplant.py b/hgext/transplant.py
--- a/hgext/transplant.py
+++ b/hgext/transplant.py
@@ -363,7 +363,7 @@ class transplanter(object):
                 inmsg = True
                 message.append(line)
         if None in (user, date):
-            raise util.Abort(_("filter produced garbled log file"))
+            raise util.Abort(_("filter corrupted changeset (no user or date)"))
         return (node, user, date, '\n'.join(message), parents)
 
     def log(self, user, date, message, p1, p2, merge=False):
diff --git a/tests/test-transplant.t b/tests/test-transplant.t
--- a/tests/test-transplant.t
+++ b/tests/test-transplant.t
@@ -374,7 +374,7 @@ test transplant with filter handles inva
   $ chmod +x test-filter-invalid-log
   $ hg transplant -s ../t --filter ./test-filter-invalid-log 0
   filtering * (glob)
-  abort: filter failed
+  abort: filter corrupted changeset (no user or date)
   [255]
 
 test with a win32ext like setup (differing EOLs)