According to MSDN, automatic paging via the GridView is only supported for data sources, or for objects that implement the ICollection interface or one of its descendants (i.e. Enumerable, Dictionary, List, Queue, Stack, etc.)
A DataTable doesn't qualify on either of those counts, so your suspecion that the DataTable does not support automatic paging is correct. However, as you have learned, you can page through a DataTable programmatically. Another approach is to use the DataTable to populate a collection which supports paging.
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