# note that having a sub for this is overkill, but if you 
# need more functionality, it's easy to encapsulate here (such
# as making it case-insensitive to independant of order)

sub stringify { local $" = ""; return "@{$_[0]}" }

if (stringify([sort @array1]) eq stringify([sort @array2])) {
    # arrays are the same
}

##</code><code>##

my %matches;
while (my ($key,$value) = each %somehash) {
    # stringified arrays as keys
    push @{$matches{stringify([sort @$value])}} => $key;
}