private email addresses harvested

I have an email address for my character, known only to:
Linden Lab, SL Exchange, Google (docs), and about 5 people
who are in a Group with me here on Second Life.

Suddenly I am receiving many email attempts from some spammer outfit
located in Washington state. I am wondering, how did they harvest
my private email address? The most interesting thing is that this is
not some shotgun. It has been carefully harvested with the knowledge
that this email address is associated with Second Life.

How do I know this? It's because the spammer's computer
is attempting to masquerade as a Linden Lab server!

There seems to have been a security breach somewhere.

I'd suspect that maybe one of the individuals put me into their
Address Book on a Windows computer infected with a virus.
But I think something else is going on.
This is not some randomly harvested email address.
This spammer is trying to masquerade as Linden Labs - their email
server is specially configured for this! These facts make it seem more likely
that there has been a breach at Linden Lab, or possibly at SL Exchange.

(By the way, I don't know what they are peddling; I did not even let
the email begin to be delivered. My mail server just hung up the phone
when they came knocking. I discovered this whole thing by monitoring
the logs of my email server, noticing the offender because it was generating
many connections and doing some other things that are not correctly following
the Internet protocols for email. Spammers typically use such mis-configured
software. Looking up the spammer's domain, I found a suspicious company
allegedly in WA, listed with bogus contact information.)

This seems to have happened just recently; nobody outside the
proper parties has ever attempted to send me email at this address.
Do you think my email is public? If so, send me email to tell me how
you discovered it (and what disclosure I have not remembered).

Is anyone else seeing suspicious email like this?

Did you happen to give your email to the watch list on the auction page recently?

There's an email address for you showing in the secondlifescripters mailing list.

That's probably it.
I don't think I posted anything to it until this week,
and now all the sudden - spam!

There's only about a dozen people who ever write to
that mailing list, though. I am thinking of the effort
required for the yield for harvesting just that list.

Anyone else getting spammed?

No, never have been there.

I got a gmail account for this exact reason, I rarely see any spam except in the spam folder.

The gmail spam detection for me is nearly perfect. Every once in a while some spam shows up, maybe once or twice a month. Practically nothing that isn't spam appears in the spam folder.

I get hundreds of spams a week, if the spam detection was only as accurate as, say, yahoo's, it would be miserable because there'd be a bunch of stuff i'd feel i should open to make sure before deleting it.

With gmail's spam system I can clear out 600 spams in short order by looking at the headers only, with confidence that every bit of it was spam.

The SL mailing lists are archived on the web, but I think the email addresses are shielded in the web archive. Is that correct?