gistfile1.pl

## Prep

my $from = '[email protected]';

if (lc($self->TicketObj->RequestorAddresses) ne $from) {
    $RT::Logger->info("Ticket is NOT from $from");
    return 0;
} else {
    $RT::Logger->info("Ticket IS from $from");
    return 1;
}

######################

## Cleanup
my $cfName = 'SERVICEDESK-Key';

my $subject = $self->TicketObj->Subject;
my $cfObj = RT::CustomField->new( $RT::SystemUser ); 

if ($subject =~ /\[SERVICEDESK\] \(((SD|Listserv|LISTSERV)-[0-9]+)\)/) {
    my $key = $1;
    $RT::Logger->info("SERVICEDESK Ticket with Key $key");

    # Add the custom field
    $cfObj->LoadByName( Name => "$cfName" );
    $self->TicketObj->AddCustomFieldValue( Field => $cfObj, Value => "$key" );

    # set up search
    my $tickets = new RT::Tickets(RT->SystemUser);
    $tickets->LimitCustomField(
        CUSTOMFIELD => $cfObj->Id(),
        OPERATOR => '=',
        VALUE => $key
    );
 
    # iterate over tickets
    my $i=0;
    while (my $ticket = $tickets->Next) {
        # skip if this is us
        if ($ticket->id != $self->TicketObj->id) {
            $i++;
            $RT::Logger->info("Adding RefersTo link id " . $ticket->id . " to ticket id " . $self->TicketObj->id);
            $self->TicketObj->AddLink(Type=>'RefersTo',Target=>$ticket->id);

            # Alternative is to merge:
            # $self->TicketObj->MergeInto($ticket->id);
        }
    } # END while()
} # END if()

1;