# I didn't test this, and didn't throw it away for some reason...
package a_delegate;

BEGIN {
    # If you don't like AUTOLOAD you could also use Corions solution, but use a blacklist
    # instead of a whitelist, to ensure that you capture new superclass methods if any arise.
    my %IGNORE = map { $_=>undef } qw( new and other funcs to ignore delegation );

    for my $method (keys %Furl::) {
        next if exists $IGNORE{$method};
        die "a_delegate already provides an implementation of $method!\n"
           if exists $a_delegate::{$method};

        *$method = sub { my $self=shift; $self->{delegate}->$method(@_); };
    }

    # Your normally scheduled package stuff...
}