BEGIN {
use Log::Log4perl qw(:easy);

Log::Log4perl->easy_init(
        {
        file  => ">> /tmp/uiv2_logfile.txt",
        level => $INFO,
        },
  );

 $SIG{__DIE__} = sub {
        if($^S) {
            # We're in an eval {} and don't want to log
            # this message but catch it later
            return;
        }
        $Log::Log4perl::caller_depth++;
        LOGDIE @_;
    };
}


use strict;
use warnings;
use diagnostics;
use CGI;
use CGI::Carp 'fatalsToBrowser';
use Frontier::RPC2;
use Frontier::Responder;
use DBI;


$ENV{ORACLE_HOME} = '/vol/ora_client/product/10.2.0.2';
my $Schema = "lv";
my $conn_data="/path/to/connection_information";

open (CONNECTION_DATA, $conn_data)
        or die "Failed to open connection data file\n";
my $DBHOST = <CONNECTION_DATA>;
my $DBUSER = <CONNECTION_DATA>;
my $DBPASS = <CONNECTION_DATA>;

close (CONNECTION_DATA);

chomp ($DBHOST); 
chomp ($DBUSER);   
chomp ($DBPASS);

my $res = Frontier::Responder->new(
         methods => {
                  Get_Login =>               \&Get_Login,
                  Get_Last_Name =>           \&Get_Last_Name,
                  Get_First_Name =>          \&Get_First_Name,
                  Get_Dept_No   =>           \&Get_Dept_No,
                  Get_AltEmpNo =>            \&Get_AltEmpNo,
                  Get_Supervisor_Emp_No =>   \&Get_Supervisor_Emp_No,
                  Get_Job_Class =>           \&Get_Job_Class,
                  GetAllByLastName =>        \&GetAllByLastName,
                  GetAllByFirstName =>       \&GetAllByFirstName,
                  GetAllByFirstOrLastName => \&GetAllByFirstOrLastName
+,
                  GetAllByLogin =>           \&GetAllByLogin,
                  GetAllByDept =>            \&GetAllByDept,
                  GetAllByEmpNo =>           \&GetAllByEmpNo,
                  GetAllByDeptExtRoom =>     \&GetAllByDeptExtRoom,
                  GetAllBySupervisor =>      \&GetAllBySupervisor,
                  GetUnixContractorInfo =>   \&GetUnixContractorInfo,
                  GetManagerList     =>      \&GetManagerList,
                  GetPeopleReportingTo =>    \&GetPeopleReportingTo,
                  Get_LoginByEmpNo =>   \&Get_LoginByEmpNo
                 }
        );

print $res->answer;
[download]

To test to see if it is the cookies issue (I'm sure there can be multiple causes for this error -- but cookies is the first one I've found documented) you can clear cache on your browser, and turn on 'ask me every time' for cookies (and delete the existing cookies) and see how many times you get prompted for cookies. It's very possible that each user has multiple cookies (or generates multiple headers in general, if cookies aren't the culprit) that are causing the error. (or just browse your cookies afterward to see how many exist for your site after using the dept with 27 people)

If it's directly related to the number of people in that department, then I'd have to deduce that it's doing something for each of those people. It might be cookies, it might be some other type of header, but that has to be part of the reason.

Have you tried looking into the module code to see what it's trying to do? I don't have that module handy, but it might spill the beans as to what's going on, and perhaps there is some option to change the behavior to prevent this issue.

I looked on CPAN and found this bug for one of the Frontier modules. It talks about a 500 error, perhaps it's related to the one you are receiving. It's very possible that it's a bug in the module and nothing in your code can prevent it, which in case you'll either have to get it fixed yourself, or hope the author fixes it. I'd definitely examine the source of the module though to see if you can spot where the issue really is. Unfortunately I can't do that at the moment, but I will try to take a look later on if I can.

I hope that was helpful.