I now have Fedora 16 Thunderbird 7.0.1 running on both omen.com via tigervnc as well as my office machine locally (currently Gnome 3). On the local machine I can type the f e d o as wlowly as I wish and the autocompletion works properly. On omen.com via VMC I must type the f e d very quickly because if I don't I get the first f* listing with e d appended.