diff --git a/Library/Homebrew/migrator.rb b/Library/Homebrew/migrator.rb
index 3389d57d76..5d6f5d4e6d 100644
--- a/Library/Homebrew/migrator.rb
+++ b/Library/Homebrew/migrator.rb
@@ -27,7 +27,7 @@ class Migrator
 
   class MigratorDifferentTapsError < RuntimeError
     def initialize(formula, tap)
-      msg = if tap == "Homebrew/homebrew"
+      msg = if tap.core_tap?
         "Please try to use #{formula.oldname} to refer the formula.\n"
       elsif tap
         "Please try to use fully-qualified #{tap}/#{formula.oldname} to refer the formula.\n"