Is there a way in Dojo to keep track of active requests?

I'm thinking about something similar to Prototype:

http://www.prototypejs.org/api/ajax/responders

My apps needs to query the number of active requests at any time.

Did anyone solve this problem?

Thx

Hello,
I've searched for a while and couldn't find something that discuss this issue. If so I'm sorry for this unnecessary thread.

When adding a filteringselect widget programmatically with an existing datastore, it starts a query to the store and creates a ajax request to the server even though there is no value set. Is there a possibilty to change the onload behaviour of this widget?

The problem is that I have a form with lots of filteringselects connected to the same datastore, and the pageloading time is correspondingly very long, when it always starts a request.