"watching directory of entry file for changes" doesn't work for me

here's my configuration:

``` js
app.use('/hoodie-store-pouchdb.js', browserify.serve({
entry: './src/hoodie-store-pouchdb.js',
watch: true,
debug: true
}));
```

when I change `src/hoodie-store-pouchdb.js`, I'd expect it to be recompiled and `/hoodie-store-pouchdb.js` serving and caching the new version once done.

Am I doing anything wrong?