Another option (though maybe more effort) is to use Net::IMAP::Simple to connect to your imap server and list out the relevant messages, assuming all you needed was subject line and timestamp.
my $email_date= DateTime::Format::Mail->new->loose;
my $imap= Net::IMAP::Simple->new($host, ...) or die;
$imap->select($mailbox) or die;
@message_ids= $imap->search("(SUBJECT foo)") or die;
for my $msg_id (@message_ids) {
my $header_lines= $imap->top($msg_id) or die;
my $head= MIME::Head->from_file(\join('', @$header_lines));
my $date= $email_date->parse_datetime($head->get("Date"));
my $subject= $head->get("Subject");
printf "%s %s : %s\n", $date->ymd, $date->hms, $subject;
}
There's a bit more work to do if you have UTF-7 subject lines or need to unpack the date timestamp from the Received headers rather than the sender's date header.