[otrs] How to enable debug for smtp?

[Keith Turner]

We are still experiencing some very annoying behavior after moving to
a new SMTP account.

Agent Notifications from the Agent site and email ticket replies from
the Agent Site go through perfectly.

All the automatic notifications fail.

The otrs log says:
[Fri Aug  4 09:40:13
2006][Error][Kernel::System::Email::SMTP::Send][100] Can't send mail
to: xxx at xxx.com! Enable debug for more info!

I tried adding the code below to enable debug, to no avail, same error
message either way. I tried both  $Self->{SMTPDebug} = 1; and
$Self->{SMTPDebug} = 0;, restarting otrs between each test to the same
result.

   # debug
   $Self->{Debug} = $Param{Debug} || 0;
   if ($Self->{Debug} > 2) {
       # shown on STDERR
       $Self->{SMTPDebug} = 1;
   }
   # added by Keith
   $Self->{SMTPDebug} = 1;

So how do you enable debug? Do debug results even show up in otrs.log?
Is it perhaps in a PERL or Apache error log instead.

We are running this on a windows server.

Any help, pointers, or other information deeply apreciated.

Keith Turner