[R] Adding a symbol/value to a boxplot in R

[Marc Giombetti]

Hello everybody,

I am new to R and I am having the following problem.
I have the following boxplot:

boxplot(s$Estimate,u$Estimate,names=c("Security", "Usability"))
title(main="Estimated development time",ylab="Estimate (weeks)")

http://i35.tinypic.com/2rhw9rm.jpg

but I want to add a label or symbol for a specific value to every
boxplot. I uploaded a screenshot
of a boxplot I generated using Excel which I try to replicate using R.
In this example my dataset
"usability" which is represented in the boxplot should be compared to
another value 84 (highlighted in red)
This value is not in the dataset u$Estimate.

http://i35.tinypic.com/24n0020.jpg

Can I use some overlay per boxplot to add a specific value?

I appreciate your help!

thanks a lot,

Marc