Well, the basic principle of hashes is that there's one value to one key, so you have to cheat. In this case, just store a stringified list (e.g. using join) as the value. Untested example code: 
my @unverified_emails=('test@admin.com', '1xtrsnf');
$dbm{'notverified'}=join ",",@unverified_emails;
foreach my $mail (split /,/, $dbm{'notverified'}) {
  print "$mail is not verified!\n";
}

[download]
Joining with comma's is probably best, as I've never encountered an email address with one in it. That said, it is not actually illegal to include comma's in email addresses (as long as you escape them with backslashes, see RFC819), so there is a very small possibility you might need another string to delimit the addresses.

Update:One way to take into account backslashed commas is a negative zero width lookbehind assertion in the split regexp: /(?<!\\),/.

CU
Robartes-

In reply to Re: DBM keys/values by robartes
in thread DBM keys/values by sulfericacid

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