ListGrid doesnt display data properly (no values) with 3.1d

[d2k]

1. the *complete* SmartGWT or SmartClient version from the lower left-hand corner of the Developer Console (see FAQ for how to open Developer Console), for example, \"v8.2p_2012-04-18/PowerEdition Deployment\"

SmartGWT used: 2.5, 3.0p, 3.1d(nightly builds from: 24.04, 25.04, 26.04, 01.05)
2.5 and 3.0p is working without any problems
2. browser(s) and version(s) involved

Google Chrome 18.0.1025.162 m & Firefox 11.0

3. for a server-side problem, the *complete* logs generated during processing of the failing request (do *not* trim to just the error message)
i think this is not a server-side problem

4. for any problem processing a server response, the actual response as shown in the RPC tab in the Developer Console
see 3

5. if there is a JavaScript error, the stack trace logged in the Developer Console (see FAQ)
there is no error

6. sample code if applicable
I added some "sample" code of how we added our tables to the ListGrid. However, the problem only appears on version 3.1d.

RestDataSource ds = new RestDataSource(); 
DataSourceTextField somefield = new DataSourceTextField("id.somefield",
				"somefield");
DataSourceTextField someotherField = new DataSourceTextField("id.someotherField", "someotherField");
DataSourceTextField datecreated = new DataSourceTextField("datecreated", "datecreated");
DataSourceTextField entrystatus = new DataSourceTextField("entrystatus", "entrystatus");
ds.setFields(somefield, somotherField, datecreated, entrystatus);
setDataSource(ds);
//here is also some operationbinding stuff... i think this is not necessary for the sample

We tried the latest 3.1d nightly builds(we need the new function to export our data into excel with copy/paste) and had problems displaying Fields where embedded id's/ManyToOne relations has been used, these fields doesn't display any data at all.
Can somebody please give us a hint where the problem can be, or is it already a known bug and a fix is on the way?

thanks in advance