mutable array of immutable objects

[Jeff Thompson via Digitalmars-d]

I want to create a mutable array of immutable objects, but the 
code below gives the error shown below. It seems that "new 
immutable(C)[1]" makes the entire array immutable, but it seems I 
should be able to change the elements of an array of pointers to 
an object even though the objects are immutable. How to do that?

class C {
  this(int x) immutable { this.x = x; }
  int x;
}
void main(string[] args)
{
  auto array = new immutable(C)[1];
  array[0] = new immutable C(10); // Error: Cannot modify 
immutable expression array[0].
}