[R] Labels for Points- 2 character labels?

[ableape]

I would like to be able to label each point in a scatter plot with 
the numeric order of that point. for example, I create the following plot:

plot(e,n)
#
# now I go back and create my labels
#
for(i in 1:length(e)) {                                    # lets say e <10
        pc <- as.character(e_order[i])               # e_order has an 
integer array 1,4,3,2... which is the order of e
        points(e15[i], n15[i],pch=pc)                # this will plot 
0-9 as data labels

      }
#
The above works for single characters.  Now if the length of e[] is 
greater than 9, the character string converted by as.character will 
yield more than one digit. At this point, my labeling trick fails:-(

1) is there a way to create two character labels for a plot?
2) Or even better, is there a way to do what I am trying to 
do.  Label each point by its numeric order?

Thanks for your help.

Renaldo