gmail phishing warnings

[Scott Webster]

Hello all.  For some time now (months?) Google's Gmail has been
displaying warning messages on all list traffic from people with a
Gmail email address.  An example screenshot can be viewed at this url:

http://www.phas.ubc.ca/~swebster/gmail.png

They recently updated the colour to a more alarming red, which
reminded me to inquire about this.  The warning seems to originate
with the fact that the message is "From:" a Gmail user but is not
actually sent to the recipient (e.g. me) directly by that user, but
instead via the list.  Google has posted some basic information about
this here:

https://support.google.com/mail/bin/answer.py?hl=en&answer=185812&ctx=mail

Anyway, my question is, is the macports list server doing anything
"wrong" with respect to the email headers?  Or is Google just being
ridiculous about this?  If it's determined that we can or should do
anything about this, I am willing to help test.  I don't recall seeing
this on any other list, but I don't subscribe to many.

Sorry if this is somewhat off-topic or just Google's fault.  It's not
really that big a deal...

Scott