- Change date and time format: Display date format can be changed in Thunderbird by following method.
- Goto Edit –> Preferences –> Advanced –> General –> Config Editor
- Create following integer strings, if not present.
mail.ui.display.dateformat.today (value 0)
mail.ui.display.dateformat.thisweek (value 1)
mail.ui.display.dateformat.default (value 1)
- see more details at http://kb.mozillazine.org/Date_display_format