thunderbird

Profile manager を使って、切替えるのが良いかな。

thunderbird -ProfileManager

Windozeなら

"C:\Program Files\Mozilla Thunderbird\Thunderbird.exe" -ProfileManager

/usr/local/thunderbird/defaults/pref/mailnews.js の中の mail.password_protect_local_cache を true にすれば良い。

--- mailnews.js~        2005-06-01 19:50:25.000000000 +0900
+++ mailnews.js 2005-07-26 10:40:11.000000000 +0900
@@ -578,7 +578,7 @@
 pref("mailnews.mark_message_read.delay.interval", 5); // measured in seconds

 // require a password before showing imap or local headers in thread pane
-pref("mail.password_protect_local_cache", false);
+pref("mail.password_protect_local_cache", true);
 // to reduce forking in the js / C++
 // overridden by stand alone mail
 pref("mail.standalone", false);

Windoze の thunderbird でも同様。

ftp://ftp.mozilla.org/pub/mozilla.org/thunderbird/releases/