Doesn't happen for me with following code.

use strict;
use warnings;

package Package1;
use Data::Dumper;

sub some_other_method {
    print Dumper @_;
}

package Package2;
our @ISA = 'Package1';

sub some_other_method {
    die "Shouldn't be called!";
}

sub quick_method {
    return shift->SUPER::some_other_method(@_);
}

sub new {
    bless {}, shift;
}

Package2->new->quick_method( 1, 2, 3 );
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It returns (correctly) following result (I've checked it in Perl v5.8.8, v5.10.1, v5.14.2, v5.16.1 and blead).

$VAR1 = bless( {}, 'Package2' );
$VAR2 = 1;
$VAR3 = 2;
$VAR4 = 3;
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But, I think that so simple code won't show the bug - it happens in more complex cases (the warning you have got is internal Perl warning you should never see, but you saw according to perldiag - this is possibly a Perl bug). If you can, try to make testcase which shows the bug happening (by shortening the program to only have what you need to show bug). Also, there is chance that some XS module breaks something.