Joined Data Source - Fields comes as non editable

Hi,

I am using Sharepoint designer 2010. My requirement is to show data from 2 lists and show it in one data form. Data from one list needs to be editable and data from another list should be non editable.

For this I used the Joined data source and was able to insert into the Data form web part. But for some reason only the initial fields that are inserted hwen I created the data form are showing as editable. The remaining fields I add are all non editabled(Coming in the Text format only).

Is there any way that I can enter data from 2 list and have editable and non editable fields in teh same dataform web part?

Regards