How to instantiate an instance of type represented by type parameter in Scala

example:

import scala.actors._  
import Actor._  

class BalanceActor[T <: Actor] extends Actor {  
  val workers: Int = 10  

  private lazy val actors = new Array[T](workers)  

  override def start() = {  
    for (i <- 0 to (workers - 1)) {  
      // error below: classtype required but T found  
      actors(i) = new T  
      actors(i).start  
    }  
    super.start()  
  }  
  // error below:  method mailboxSize cannot be accessed in T
  def workerMailboxSizes: List[Int] = (actors map (_.mailboxSize)).toList  
.  
.  
.  

Note the second error shows that it knows the actor items are "T"s, but not that the "T" is a subclass of actor, as constrained in the class generic definition.

How can this code be corrected to work (using Scala 2.8)?