RadToolBar for ASP.NET AJAX Version Q3 2008 released 11/25/2008 (release history)

You can use the PostBackUrl property of the RadToolBar object to make the button items postback to a page different than the current one. On the second page, you can access the controls of the page, from which you have been redirected, by accessing the second page's Page.PreviousPage property.

You can set the PostBackUrl property of the button items (RadToolBarButton, RadToolBarSplitButton) to override the PostBackUrl property of the RadToolBar.

    
    <telerik:RadToolBar runat="server" ID="RadToolBar1" PostBackUrl="CrossPageCS.aspx" ... />