Extra List in 3.1.6-test1

[Vin Shelton <acs@xxxxxxxxxxxxxxxxxxxx>]

I'm getting an extra list with ambiguous completion in 3.1.6-test1.
3.1.6-test1 with no patches applied.  Start with a clear screen.

: ~ Wed 14 11:56; zsh -f
dusk1% uname -a
SunOS dusk1 5.5.1 Generic sun4m sparc
dusk1% echo $ZSH_VERSION
3.1.6-test-1
dusk1% setopt noalwayslastprompt
dusk1% echo $ZSH_<TAB>

# So far, so good.
# This results in the screen looking like:

: ~ Wed 14 11:56; zsh -f
dusk1% uname -a
SunOS dusk1 5.5.1 Generic sun4m sparc
dusk1% echo $ZSH_VERSION
3.1.6-test-1
dusk1% setopt noalwayslastprompt
dusk1% echo $ZSH_
ZSH_NAME      ZSH_VERSION   
dusk1% echo $ZSH_


# When I now press another <TAB>, I get 'ZSH_NAME', offered as the first 
# completion, but I get an additional list, so the whole screen now
# looks like this:

: ~ Wed 14 11:56; zsh -f
dusk1% uname -a
SunOS dusk1 5.5.1 Generic sun4m sparc
dusk1% echo $ZSH_VERSION
3.1.6-test-1
dusk1% setopt noalwayslastprompt
dusk1% echo $ZSH_
ZSH_NAME      ZSH_VERSION   
dusk1% echo $ZSH_NAME
ZSH_NAME      ZSH_VERSION   
dusk1% echo $ZSH_NAME


I didn't used to get the extra list; was the change intentional?
I don't like it.  How can I get the old behavior back?

TIA,
  vin

-- 
In a minute there is time
For decisions and revisions which a minute will reverse.         T.S. Eliot