diff --git a/tools/bundler.js b/tools/bundler.js
index c26b307351..8368e3b3ab 100644
--- a/tools/bundler.js
+++ b/tools/bundler.js
@@ -187,9 +187,9 @@ _.extend(PackageBundlingInfo.prototype, {
       return;
     self.files[where][rel_path] = true;
 
-    var ext = path.extname(rel_path).substr(1);
-    var handler = self.get_source_handler(ext);
-    if (handler) {
+    var ext = files.registered_file_extension(rel_path, self.api.registered_extensions());
+    if (!! ext) {
+      var handler = self.get_source_handler(ext.substr(1));
       handler(self.bundle.api,
               path.join(self.pkg.source_root, rel_path),
               path.join(self.pkg.serve_root, rel_path),
diff --git a/tools/files.js b/tools/files.js
index bbe6bde871..9827ac9599 100644
--- a/tools/files.js
+++ b/tools/files.js
@@ -85,7 +85,7 @@ var files = module.exports = {
                                   extensions, func);
           });
         });
-      } else if (_.indexOf(extensions, path.extname(filepath)) !== -1) {
+      } else if (!! files.registered_file_extension(filepath, extensions)) {
         func(filepath);
       }
     });
@@ -101,13 +101,29 @@ var files = module.exports = {
         ret = ret.concat(files.file_list_sync(
           path.join(filepath, fileName), extensions));
       });
-    } else if (_.indexOf(extensions, path.extname(filepath)) !== -1) {
+    } else if (!! files.registered_file_extension(filepath, extensions)) {
       ret.push(filepath);
     }
 
     return ret;
   },
 
+  // Given a path, return his file extension.
+  // Return false if there are no registered extensions that match.
+  // This function support multiple extensions such as `.coffee.md`
+  // unlike the node native `path.extname` function
+  registered_file_extension: function(filepath, extsList) {
+    parts = filepath.split('.');
+    ext = "";
+    for (var i = parts.length - 1; i > 0; i--) {
+      ext = '.' + parts[i] + ext;
+      if (_.indexOf(extsList, ext) !== -1) {
+        return ext;
+      }
+    }
+    return false;
+  },
+
   // given a path, returns true if it is a meteor application (has a
   // .meteor directory with a 'packages' file). false otherwise.
   is_app_dir: function (filepath) {