use Crypt::RSA;

my $message="This is a sample message.";
my $rsa = new Crypt::RSA; 
my ($public, $private) = 
        $rsa->keygen ( 
          Identity  => 'Piyush Shourie <piyush_shourie@infosys.com>',
          Size      => 1024,  
          Password  => 'A day so foul & fair', 
          Verbosity => 1,
      ) or die "1".$rsa->errstr();