bug#7123: 23.2; large blank left margin with variable-width font

[Bill Richter]

In GNU Emacs 23.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)
 of 2010-09-28 on poisson.math.northwestern.edu
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--with-xpm=no' '--with-jpeg=no' '--with-gif=no' 
'--with-tiff=no' '--prefix=/rhome/2/richter/gnu''

I just made emacs in dir emacs-23.2 on Scientific Linux, and typed 

src/emacs -Q -fn -adobe-helvetica-medium-r-normal--24-240-75-75-p-130-iso8859-1 
&

There is a large blank left margin no matter what buffer I am editing.
Right now it comes out as far as the 2nd u in 
U:** - *mail to bUg-gnu-emacs@gnu.org*:
 in the minibuffer.

My experiments indicate that this bug occurs with any variable-width
font, and it never happens with a fixed-width font.