C# - How can I "overload" a delegate?

First, I was reading some forums and the help in MSDN and all says that a delegate can't be overloaded.

Now, I want to have something like this:

public delegate void OneDelegate();
public delegate void OneDelegate(params object[] a);

public void DoNothing(params object[] a) {}
public void DoSomething() { /* do something */ }

private OneDelegate someFunction;

someFunction = new OneDelegate(DoSomething);
someFunction = new OneDelegate(DoNothing);

So, like you know, you CAN'T do this, because OneDelegate only refers to the first one and not the second one. But, is there a way for doing this? or something like that?

PS1: I want to have any number of OneDelegate declarations, not just one or two.