[Rd] family="mono" does not work (PR#12931)

[jaanvajakas at hot.ee]

Full_Name: Jaan Vajakas
Version: 2.7.2
OS: Windows XP
Submission from: (NULL) (193.40.5.245)


When I execute the following code in the R GUI, the text "mono" is printed in
monotype font in the first plot, but in normal (sans-serif) font in the
remaining three plots:

op=par(mfrow=c(2,2))
for (i in 1:4) {
 hist(1:10,xlab="")
 mtext("normal",side=1,line=2)
 mtext("mono",side=1,line=3,family="mono")
}
par(op)