TAbControl, UserControl, Datacontext Problem

Hi,

i use c#, .NET Framework 4.5 and wfp to build my applications. Now i have a big problem with my datacpntext.

Visual Try:

MainWindow - Grid - RadTabControl - UserControl1 - Grid - Frame - UserControl2 - Grid - RadGridView.

the reason behind my issue is the fact that the command is exposed by the DataContext of the RadTabItem and the actual DataContext of the button is the DataContext of the RadGridView control (in the initial project). Hence the binding of the Command property of the Button cannot find the referenced command as it is defined in the DataContext of the parent of the RadGridView (the business item representing the RadTabItem) rather than in the DataContext of the RadGridView itself.
      
But how do i solve this problem?

Thanks
R