I recently did a system wipe and installed Thunderbird 3.0, and imported all of my email setup from a previous Thunderbird 2.0 installation. Almost everything is working fine, but I'm having a problem with the autocomplete in email addresses when writing messages.

The relevant behavior is this: In the old 2.0 installation, the autocomplete appeared to know which email addresses I used most frequently, and so when I typed "m" in the address line, it would pick as the default selection the "m"-person who I frequently write email to. (It's possible this is an illusion and it simply picked people in the order I added them to my address book.) Thus, I have become used to typing "m"-"enter" in the address field, and getting this person.

In the current 3.0 installation, however, the autocomplete order has changed. It's not the same as it was, and it's not alphabetical. The result is that I'm spending extra time looking at the email address bar, and more annoyingly, half the time the old muscle-memory kicks in and I find myself with an email that's addressed to a couple of customers rather than to my boss and coworker.

Thus, two questions: How does Thunderbird determine this autocomplete order, among a set of addresses all of which are in the same address book? How can I change this ordering to be what I want?

(I have tried Google-searching, and found a number of incomplete answers, nearly all of which were for version 1.0 or thereabouts, and reference settings dialog boxes that no longer exist.)