Tabbing between fields on vbulletin login page is confusing.
1) Go to http://www.defensivecarry.com/vbulletin/ while not logged in
2) Enter user name in the username field at the top
3) Press <tab>
-> The page jumps to the bottom, with the lower "username" field selected.
Pressing <tab> again jumps to: "Password" at top, "Password" at bottom, "Remember" at top, "Remember" at bottom.
(tested in Google Chrome only.)