if( ref( $obj ) eq $type ) { ... 
## or
if( $obj =~ m[=$type$] ) { ... 

##</code><code>##

if( ref( $exception ) eq $type )
or grep{ ref( $exception ) eq $_ } @{ $type::ISA } ) {  ...
## or
if( $exception =~ m[=$type$]
or grep{ $exception =~ m[=$_] } @{ $type::ISA } ) {  ...

##</code><code>##

use Exception::Class (
    'MyException',

    'AnotherException' => {
        isa => 'MyException'
    },