Logout - Master Pages - Register Script Error

[Mark]

We have main Master Page with other Master Pages derived from it with the content pages then underneath.
On the main Mater we have a logout control. I placed the RadScriptManager on the main Master page but when I log out I get

Script controls may not be registered before PreRender.

[InvalidOperationException: Script controls may not be registered before PreRender.] System.Web.UI.ScriptControlManager.RegisterScriptControl(TScriptControl scriptControl) +236 System.Web.UI.ScriptManager.RegisterScriptControl(TScriptControl scriptControl) +99 Telerik.Web.UI.RadDataBoundControl.RegisterScriptControl() +41 Telerik.Web.UI.RadPanelBar.OnPreRender(EventArgs e) +34 System.Web.UI.Control.PreRenderRecursiveInternal() +86

Suggestions?

[Mark]

I have resolved this by explicitly adding:

 

FormsAuthentication.SignOut();

 

 Response.Redirect(

login page  true);

in the LoggingOut event handler