[Rd] plot, spineplot, boxplot in R 2.2.0

[Gabor Grothendieck]

I noticed, what seened to me, to be odd.  These produce
a boxplot in the first case and a spineplot in the second
case in R .2.2.0:

plot(Sepal.Length ~ Species, iris)
plot(Species ~ Sepal.Length, iris)

What if one wants to exchange axes?  Does the fact that
this seemingly innocuous change result in completely
different graphics make sense?  Is it desirable?