Sort GridView Bound to DataTable

I have a repository that contains all of my LINQ queries for this project that I am working on. I am able to get the LINQ results to a DataTable and bind that to a gridview for displaying the data. Now I need to make the gridview sortable. I have set AllowSorting="true" and I have the OnSort event handled in a routine in the codebehind. The program makes it into the sorting routine just fine.