ListView pagination problem.

Trying to quickly create paginated grid. So i am using ListView.
Unfortunatelly pagination works a little strange.
Pagination control appears correctly.

But when i click "2" page postback happens but current page is still first
page. Then i click "3" page. Postback happens but current page is now "2"
page. Then i click "4" page and again postback happens and page 3 becomes
current.

Why is that? How to make it work?
Bellow you can find my code (Nothing else like code or any other control is
on the page)

thanks
George.

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protected override void OnInit(EventArgs e)
{
if( !isPostBack )
{
grdItems.DataSource = clsGlobal.GetData("SELECT Id,Name FROM
tblMy");
grdItems.DataBind();
}
}
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