[ESS] auto-complete working in inferior-ess-mode but not ess-mode?

[Vinh Nguyen]

Hi,

I'm currently using the bleeding edge version of ESS on Emacs 24.5.1
in Windows 7.  I have the following in my init file to enable
auto-complete:

(setq ess-use-auto-complete t)

In an iESS buffer (iESS [R]), auto-complete works (type "plot." in the
prompt and a list of possibilities is displayed).  I also see a
drop-down menu named "Complete".

However, within an R file (ess-mode; ESS[S]), auto-complete doesn't
work (eg, when I type "plot." like before).  I don't see the
"Complete" drop-down menu either.  When I run the function
(auto-complete-mode), the mode gets disabled, meaning that it was
enabled before.

Any thoughts on what's going on and how I could fix this?  Thank you.

-- Vinh