R devel - Sep 2014 - Regression and inconsistency of width of apostrophes in R vignettes

My main dev machine died a well-deserved death a few weeks ago after six
and a half years of faithful service, and refused to be re-animated. A
substantial
part of setting up its replacement is re-running a lot of R vignettes (mostly
for timing to establish new performance baselines) - and also
cleaning away some such vignettes generated in the past under different
versions of R.

So I noticed a regression of behavior between R 2.x and 3.x/current. The width
of apostrophes in code output was working correctly in R 2.x and is wrong in R
3.x
generated vignettes. Specifically, it affects summary(data.frame) with some
columns
that contains NA's. Here is an edited example snipplet (you should view this
with
fixed-width font terminal):

================\begin{Sinput}
> summary(some.data.frame)
\end{Sinput}
\begin{Soutput}
      P.BB             z.HWE         
 Min.   :0.00000   Min.   :-3.83163  
 1st Qu.:0.07071   1st Qu.:-0.56856  
 Median :0.26263   Median : 0.18426  
 Mean   :0.33754   Mean   : 0.06581  
 3rd Qu.:0.56566   3rd Qu.: 0.73845  
 Max.   :0.98990   Max.   : 3.73120  
                   NA's   :2         
\end{Soutput}
================
In R 2.x generated pdf's, the ":" all lined up. In R 3.x/current
generated pdf's, the "NA's"
is typesetted with a narrower apostrophe and therefore the ":" no
longer line
up properly.

This is running both versions in parallel on the same system so there is no
LaTeX related
issue in the rest of the system. I see Prof Ripley is the person to have changed
R Sweave's behavior in the last few years, and all the recent changes are to
do with
quotes (which probably means apostophes also) I suspect the relevant change is
probably
r63858 (and its equivalent r63864 in the R-3.0 branch) although I'd be happy
to be
corrected. In any case, the above new behavior of summary(data.frame)
columns not lining up seems to be undesirable so I'd prefer reverting to the
older
appearance, unless there is a good reason; or at least identify what
local quirks I have which results in this, if I am the only person experiencing
this difference
of behavior between R 2.x and R 3.x.

------------------------------------------------------------------------
r65917 | ripley | 2014-06-11 11:46:03 +0100 (Wed, 11 Jun 2014) | 2 lines

prefer zi4.sty, use [noupquote] only with that

------------------------------------------------------------------------
r65748 | ripley | 2014-05-26 08:39:14 +0100 (Mon, 26 May 2014) | 2 lines

use [noupquote]

------------------------------------------------------------------------
r63858 | ripley | 2013-09-07 07:02:08 +0100 (Sat, 07 Sep 2013) | 3 lines

add inconsolata option to Sweave
Arrange for '' and `` to render in the same way in \code, \samp as
\examples.