Your second example looks more correct, but in fact should be: 
foreach my $parent (@LWP::UserAgent::Determined::ISA) {
    if ($parent eq 'LWP::UserAgent') {
        $parent = 'LWP::UserAgent::Proxified';
        last;
    }
}

[download]
instead of push.
Module can automate this routine actions and make some additional checks.

In reply to Re^2: base class manipulation: Is there something similar on CPAN? by OlegG
in thread base class manipulation: Is there something similar on CPAN? by OlegG

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