Mail 5.0 wrong received dates

[LxHunter]

Mail 5.0 is showing I have received email today as received on January 12, not October 12. All my mail received dates are marked as January - even if they are another month.

This has happened to my Gmail accounts and my ISP email accounts.

I have searched the Web but found no info on this problem.

Any ideas what I should do?
Thanks

 

[LxHunter]

Oh, duhh, fixed it.
Went to Preferences>Languages & Texts>Formats.
The "Region" was set to "Custom" for some reason.
Changed it to "Canada" and fixed the Problem