MouseEventGroup binding problem

I’m trying to MouseEventGroup:

        <s:ModifierGroup s:MouseManager.MouseEventGroup="{Binding SharedMouseGroupId}">

Where SharedMouseGroupId is

    private String sharedMouseGroupId;
    public String SharedMouseGroupId
    {
        get { return this.sharedMouseGroupId; }
        set
        {
            this.sharedMouseGroupId = value;
            RaisePropertyChanged(() => SharedMouseGroupId);
        }
    }

And init:

        SharedMouseGroupId = Guid.NewGuid().ToString();

But this doesn’t work.
If i subscribe on Loaded event of surface and manually set MouseEventGroup, this work.

        MouseManager.SetMouseEventGroup((DependencyObject)c.ChartModifier, ViewModel.Parent.SharedMouseGroupId);