Label / Tick under single Boxplot

Hi!

I am trying to get the tick / label under a stacked
boxplot with only a single 
data row. With >=2 rows it works, but with a single
one the tick resp. my class 
name is not printed below the boxplot. Can anybody
point me to what am I doing 
wrong?

For example:
boxplot(data.frame(c(3,4,5)),names=list("a"),beside=F)

Here, I would like to have the "a" below the single
box.

Thanks a lot,
   Werner

using R 2.0.1 on Win2K