DataTable Sorting

Question

Initial DataTable values

Group  Col2  
====== ====
 null  21
 G     22
 null  23
 G     30
 G     31  

I want to order the Datatable so that it has :

Group  Col2  
====== ====
 null  21
 G     22
 G     30
 G     31
 null  23 

basically since value 22 has Group 'G' , all the rows in the same group are immediately after 22.

Is there any way this can be done using a DataTable without looping thru the rows?

I am using C#. Its a disconnected DataTable.

Thanks in advance!