Silverlight Dockpanel missing in toolbox

I have installed Silverlight3_tools and Silverlight_sdk and still unable to find DockPanel in the toolbox. Both the installers installed without asking for a save location. How do I find the reference now开发者_如何学运维?

I am using VS 2008 SP1 on win XP sp2

Thanks for any help..

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The DockPanel is found in the Silverlight Toolkit. For Silverlight 3 you will need the Nov09 Toolkit.