Module1 
Use threads;
Use threads::shared;
Use Module 2;

sub thread_it 
{   
   Code that uses threads/threads::shared 
}

sub fork_it
{
   my $mod2 = Module2->new()
   $mod->fork_it()
}

##</code><code>##

Module2
Use forks;
Use forks::shared;
sub fork_it
{
   code that runs forks here
}

##</code><code>##

my $mod1 = Module1->new()
$mod1->fork_it()
$mod1->thread_it()