Mac Mail displays wrong time

Actually I don;t think that is Melissa's problem. She is probably like me and finds that the mail on the iPhone shows incorrect times, almost like it is the wrong timezone or something. However, when I look directly on the mac.com server the times are correct (for my timezone). I have timezone support on and have set my timezone on the iPhone. The time display is correct, just the messages in mail are wrong...

The date & time that Mail shows in the Date Received column is the date & time that appears in the latest (topmost) Received message header (which you can see doing View > Message > Long Headers), and is set by the recipient’s incoming mail server. Thus, if this date & time is wrong, then it’s your incoming mail server’s fault.

The date & time that appears in the Date message header is set by the sender’s mail client and is what Mail shows in the Date Sent column, not what it shows in the Date Received column.

Since installing Leopard Mail reports the mail received in January (the correct date but always January) hence today 10 December is reported as 10 January. It is reported correctly on the webmail of my email provider. It is just Mail that puts the wrong month.

I am having the same issue.
A few months back I upgraded my home G4 to Tiger from Panther (because I like to stay current)

Was thrilled with the upgrade overall, but in Mail, I noticed my work email was time stamped 5 hours ahead. Didn't think much of it because I only have my work email at home for occasional convenience. My home email (dotMac) is normal.

Last week, I finally convinced IT to let me upgrade my work computer to Tiger - they were a bit nervous to leave Panther behind.

So now I'm noticing that my work email here is ALSO stamped 5 hours off (my dotMac is still fine.) Only here at work, it is a bit more of a problem to have my email time stamped wrong.

I checked the mail preferences, I had IT check the server settings at work, on my work email, I can't find the problem. I am in Eastern zone, so GMT -0500, I suppose it's possible that Mail has somehow defaulted to GMT 0. But I can't imagine why. And why in Tiger but not Panther? And where else can I change the date other than in system preferences?

Here is an earlier thread on the topic which seems to establish that Mail is failing to subtract the given time from the GMT/UTC stamp in the email headers for a POP account.
http://discussions.apple.com/thread.jspa?messageID=6003127&#6003127
But no solution was found.

Any thoughts?

It should be noted that on both machines, the incorrect time-stamping starts at exactly the time and date I upgraded from Panther to Tiger. On the computer I'm on now, I can see that everything prior to the morning of January 24th is correct. I did my upgrade over lunch on January 24th, and in the afternoon of the 24th, Mail is 5 hours off.

I also chose the upgrade path, not a clean install.

I have the very same problem... only is 8 hours off for me. (PST)
The odd thing is that some Tiger systems are doing it and others are not...
My Leopard system shows the proper time stamp.

All of my message prior to doing the Leopard upgrade were correct upon receipt with mail passing through the exact same mail server.