The problem seems to be that the form that actually accepts the username and password is https://ib.nab.com.au/nabib/index.jsp
but this cannot be entered directly into the browser, and can only be accessed in a usable form if this page has been referred from the login menu on https://www.nab.com.au/
. This may have useful security implications although if so they are obscure to me.
So to achieve a login from LastPass, edit the entry to have https://www.nab.com.au/
as the URL, your username and password in the proper fields and then click this. Then you will have to click login and "Internet Banking". In the https://ib.nab.com.au/nabib/index.jsp
page that follows your username and password will autofill if set to do so, and you can log in.
No, it is definitely not a one click login, but this appears to be the best achievable while the NAB has its current login scheme
(All this using Firefox with Last Pass Plugin)