$ cat Foo.pm
use strict;
use warnings;
package Foo;
use Carp qw/ croak /;

sub foo {
    eval {
        Baz::bar();
    };
    my $e = $@;
    print "\$\@ = '$e'\n";
    $e =~ s/(.*) at .*\n/$1/;
    croak $e;
}

package Baz;

sub bar {
    die "blubb";
}

1;
$ perl -wle'
use Foo;
Foo::foo();'
$@ = 'blubb at Foo.pm line 19.
'

blubb at -e line 3

#!/usr/bin/perl

use strict;
use warnings;
use Encode;

eval{
encode('mein_utf','test');
};

print '$@ ist nicht leer' if $@;

C:\>encode_die.pl
$@ ist nicht leer

package module;
use strict;
use warnings;
use Carp qw( croak carp );
use Encode;

sub new {
    my ( $class, @args ) = @_;
    my $self = {};
    bless $self, ref( $class ) || $class;
    return $self;
}

sub foo {
    my ( $self ) = @_;

    if ( !eval { encode( 'utf-no', 'text' ) } ) {
        croak(
            "Laenge der Meldung: " . length($@),
            "\nMeldung: " . $@
        );
    }
}

1;

#!/usr/bin/perl
use strict;
use warnings;
use module;

my $mod = module->new;

$mod->foo();

Laenge der Meldung: 47
Meldung: Unknown encoding 'utf-no' at module.pm line 17
 at script.pl line 8