How can I resolve the "could not find function vapply" error in R?

I installed the stringr package on my Ubuntu 10.04 machine under R 2.10.1. When I try to use the str_extract() function R stops and gives the following error message:

Error in recyclable(string, pattern, replacement) : could not find function "vapply"

How can I solve thi开发者_C百科s problem? Is there any specific package that contains this vapply function?

vapply is in the base package, so something may be wrong with your installation.

I'm using Ubuntu and I think the problem is that it's using an older version of R in the repos. I uninstalled R from my machine, then I used this http://www.keittlab.org/node/158 to set up the repos for R. So far this works for me very well.