expressjs - error handling for POST requests

I am trying to register an error handling middleware in the standard way:

app.use(function(err, req, res, next){
    //do something with the exception    
});

It works fine for my get requests, but not for , i.e. when an error is thrown in processing of a post request, then the middleware is not invoked and the whole app crashes.

How do I register an error handler for post requests?