Hi Richard,
I don't see anything obviously wrong in your code. Are you sure it is "Fob Table" and not "FobTable".
You can also try passing table instead of DataSet, e.g.
ultraGrid.SetDataBinding(tableObject, null, true);

Here is the link to Infragistics Knowledge Base, that I've found when I was after that problem. You may setup a new clean example, try that and after that compare with your code.

http://devcenter.infragistics.com/Support/KnowledgeBaseArticle.Aspx?ArticleID=6702

Regards,
Nick