new class from variable

[Anon]

I need to make a new copy of some of my classes. I want to pass the name of the class through a variable. Like this

<?php
class class1{
..........
..........
}

class class2 extends class1{
..........
..........
}
$array(
1=>'class1',
2=>'class2'
)

$new_class=new $array[1];
?>
This is NOT works. it prints
Fatal error: Cannot instantiate non-existent class
Is there any way to escape this problem?

[Anon]

i've found the solution.
i've used such construction to make a copy

$this->prod=new $this->type_class();

And the solution IS!!
$str=$this->type_class();
$this->prod=new $str;
MayBe it'll be helpfull for somebody