#!/usr/bin/perl
use warnings; use strict;
my %hash;
$hash{"eins"}{"subeins"} = "hallo 1";
$hash{"eins"}{"subzwei"} = "welt 1";
$hash{"zwei"}{"subeins"} = "hallo 2";
$hash{"zwei"}{"subzwei"} = "welt 2";
&probiere($hash{"zwei"});
exit;
sub probiere {
    my $myhashref = shift;
    print %{$myhashref}{"subeins"};  # klappt nicht
}