Add custom values to dsRequest

SmartClient Version: v9.0p_2014-02-24/LGPL Development Only (built 2014-02-24)

I can use the ListGrid with RestDataSource and with Http POST+JSON.

But how can I add some extra JSON values to the POSTed data?

I tried in transformRequest(DSRequest dsRequest):
Map p=new HashMap();
p.put("p1",1);
p.put("p2",2);
dsRequest.setParams(p);
...
return super.transformRequest(dsRequest);

But this add the (p1&p2) parameters to the HTTP request URL as parameters.
I want add these parameters in request body as JSON values. Like startRow,endRow, etc...


How can I do this?

Thx