delete a dynamic array

[tsalm]

Hello,

It's certainly a stupid question...

I want to delete an dynamic array of the memory.
I don't understand why the example above doesn't clear the memory uses by  
the array :

/* ------------------------------- */
import tango.time.Time;
import tango.io.Stdout;
import tango.stdc.stdio;
import tango.core.Memory;

void main()
{
  // Create a big array
  int[] t = new int[100000000];

  // delete the array
  t = null;

  // Clean the memory
  GC.collect();
  GC.minimize();

  // No, it's not free :-(
  Stdout("Now, the memory must be free...")();getchar;
}

/* ------------------------------- */

How can I totally clear this array of the memory ?

Thanks in advance,
TSalm