linq query ordering

I have a linq query that creates an anonymous type. I order the linq according to a dynamic setting. I then convert this to a list. When I bind this to a gridview, the ordering is lost. What am I doing wrong? Here is some code:
 
Public Function GetContacts(ByVal sortExpression As String) As IEnumerable Dim contactsQuery = From con In context.Contacts Join cus In context.Customers On con.customerID Equals cus.customerID Select con.contactTel1, con.customerContactID, con.contactTel2, con.contactEmail, con.contactName, cus.customerName, cus.customerID Order By sortExpression 'The follow returns the list, but the sortExpression is ignored Return contactsQuery.ToList
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