Sorting gridview with membership data

[Arjen]

Hi,

I databind my gridview like this:
GridView1.DataSource = Membership.GetAllUsers(); // asp.net 2.0
(MembershipUserCollection)
GridView1.DataBind();

When I try to sort the gridview I get this error message:
The GridView 'GridView1' fired event Sorting which wasn't handled.

What do I need to do to get it work?
(Can you give me an example)

Thanks!