How to inject dependencies into view models in Caliburn.Micro?

I really hope this is not a stupid question, but I'm somehow unable to recognize a straight-forward way to inject dependencies into view models using Caliburn.Micro.

I'm having a main shell (conductor) like so:

public class ShellViewModel : Conductor<IScreen>.Collection.OneActive, IShell
{
    public ShellViewModel(IEventAggregator eventAggregator) {
        ActivateItem(new DashboardViewModel());
    }
}

Now I'd like to inject a service into the DashboardViewModel but since the ActivateItem method requires me to pass an instance (rather than e.g. a type), I'm forced to provide the service myself. And since the ShellViewModel isn't aware of an underlying IoC container, I have to have the service injected into the shell.. to me, it looks like Caliburn is trying to enforce a complete graph of all view models and dependencies within an application.

I am aware that I could use a static accessor for my inversion of control container, but I really don't like this approach because I'd like to have a single composition root for my application (the bootstrapper) without having the other parts knowing about dependency injection and such.