diff --git a/lib/coffee-script/repl.js b/lib/coffee-script/repl.js
index a2e4e57d..901a91a5 100644
--- a/lib/coffee-script/repl.js
+++ b/lib/coffee-script/repl.js
@@ -145,6 +145,7 @@
         console.warn("Node 0.8.0+ required for CoffeeScript REPL");
         process.exit(1);
       }
+      require('./extensions');
       opts = merge(replDefaults, opts);
       repl = nodeREPL.start(opts);
       repl.on('exit', function() {
diff --git a/src/repl.coffee b/src/repl.coffee
index 59696f4d..d9d0298a 100644
--- a/src/repl.coffee
+++ b/src/repl.coffee
@@ -131,6 +131,7 @@ module.exports =
       console.warn "Node 0.8.0+ required for CoffeeScript REPL"
       process.exit 1
 
+    require './extensions'
     opts = merge replDefaults, opts
     repl = nodeREPL.start opts
     repl.on 'exit', -> repl.outputStream.write '\n'