This thread deals with the same situation, by using CommandReferences from the
MVVM toolkit. Another possible option is using
commands with attached behaviors (you can use
this code snippet to create the attached behavior).
You can download a small sample application from
here, using attached behaviors. Take into account that for this to work, the window/view where you want this to work must have
KeyboardFocus (you can check this by having a textbox in the view and focusing on it).
Please let me know if this helps.